Hi everyone.
Sedan stops reving at 3k rpm. As if it has a rev limiter. Feels like its running out of fuel - running lean.
New plugs, coil, fuel pump, points.
Starts great, idles great, runs great but when i hit 3k it bogs down as if its gonna die, with or without load, misfire.
Before I start working on carb/fuel and timing is there anybody else that had an issue similar to this?
Thanks everyone.
cant rev over 3k rpm
-
Bryan O_Shaughnessy
- Posts: 36
- Joined: Mon Feb 10, 2014 5:33 am
Re: cant rev over 3k rpm
1) Possibly you have air leaking into the intake system somewhere past the carburetor. Look at the connection from the carb to the cylinder head; rubber parts on a car this old will crack and let air into the fuel/air mix after the carb, causing a too-lean mixture. This happens to motorcycles often; their rubber parts are out in the sunlight where UV rays deteriorate the rubber ducts that funnel the air/fuel mix from the carburetor into the intake-valves. 2) If you've done a tune-up, check the wire-connection and ground-screw for the condenser that you installed. It's a simple mistake not to tighten the condenser strap, causing a poor ground that rattles when engine vibration gets higher. Also, try the old condenser to see if perhaps the new one was dropped and shorted before it was sold to you. It's worth removing the spark-plugs to see if either of the insulators is broken, too. Shit happens, you know. 3) Pull the car into your garage and turn off the garage lights. Remove the points-cover. With the motor running, prop-open the hood and look in the dark engine compartment to see if there is any sparking going on from the plug-wires or spark-plug connectors or the coils. Also look in the points housing and see if there is any arcing going on in there (other than the correct sparking of the points themselves). Rev-up the motor to the point where the engine starts to run poorly to see if you can cause the problem while you are looking for sparks. 4) When you shut off the engine, check to see if the vacuum advance springs are working on the points; it might run ok at low revs, but when you give the motor more gas, the weights on the advance mechanism must spread out to speed-up the motor. Start the motor again and watch the weights to see if they spread open when you rev-up the motor. 5) I've never done this, so I suggest you refer to a shop manual, but the float in the carburetor float-bowl might need replacement or adjustment. There are other symptoms that indicate this and you should read the troubleshooting section of the manual. If the float is stuck in a too-high position, it might be restricting the fuel flow, starving the engine when it needs more gas.
Whatever the problem is, it is probably very simple and basic. I hope you'll get a laugh when it's fixed. ---Bryan O
Whatever the problem is, it is probably very simple and basic. I hope you'll get a laugh when it's fixed. ---Bryan O
> From:
> "promoter213@... [anzhonda600owners]"
> To:
> anzhonda600owners@yahoogroups.com
> Sent:
> Wednesday, May 11, 2016 6:18 PM
> Subject:
> [anzhonda600owners] cant rev over 3k rpm
> Hi everyone.
> Sedan stops reving at 3k rpm. As if it has a rev limiter. Feels like its running out of fuel - running lean.
> New plugs, coil, fuel pump, points.
> Starts great, idles great, runs great but when i hit 3k it bogs down as if its gonna die, with or without load, misfire.
> Before I start working on carb/fuel and timing is there anybody else that had an issue similar to this?
> Thanks everyone.
Re: cant rev over 3k rpm
I've seen that problem many times. From the few details you have offered, I could list 100 things which would cause your problem. You seem to be telling me that rev it at a standstill and it drops off at 3K and you can drive it and it drops off at 3K and it sounds perfect at idle (is that at 1050 rpm?). With that information, I would suspect you have an ignition or airflow problem.
For the airflow problem, remove the air filter and the cover plus check the choke is open when the engine is warmed up. Does it run above 3K rpm?
For the ignition problem, look at pg 2-12 of the sedan shop manual. You will see the engine advance for a n600/z600 is about 20 degrees at 3K rpm. The T and F timing marks on the crankcase correspond to 0 degrees (T) and 10 degrees (F). Make some more marks on the pulley or the crankcase to show you where 20 and 30 degrees are located.
I would put the marks on the pulley. I would advance the pulley until the notch is at the F and then I would put a mark on the pulley at the T (a red mark). I would then advance the pulley until the red mark is at the F and put a mark on the pulley at the T (a blue mark). I would then advance the pulley until the blue mark is at the F and put a mark on the pulley at the T (a green mark).
Using a timing light, verify the crank pulley is at the F mark when the engine is at idle and see where it is at 2000 and 3000 rpm. When the red mark is at the T, I have 10 degrees of advance. When the red mark is at the F, I have 20 degrees of advance. When the blue mark is at the T, I have 20 degrees of advance and when it is at the F, I have 30 degrees of advance. When the green mark is at the T, I have 30 degrees of advance.
I suspect your ignition timing is off which is causing the engine to not rev past 3K. The problem would be in the area of the distributor housing. It could be on the breaker plate, mechanical advance, or possibly the vacuum advance arm is preventing the breaker plate from rotating properly.
Other things could cause your problems but this is what I would be checking first. I have spent more time typing this message than it would have taken me to figure out your problem if I was looking at your car.
If you don't get the problem resolved, let us know more details such as;
1) did the car rev above 3K before you worked on it
2) What other checks have you done.....engine compression, valve adjustments, spark plug gap, does your timing light flash correctly when it is connected to either spark plug wire, are your brakes working and not dragging, have you worked on these cars before with success or is this your first Honda 600 car.
good luck,
Dale
For the airflow problem, remove the air filter and the cover plus check the choke is open when the engine is warmed up. Does it run above 3K rpm?
For the ignition problem, look at pg 2-12 of the sedan shop manual. You will see the engine advance for a n600/z600 is about 20 degrees at 3K rpm. The T and F timing marks on the crankcase correspond to 0 degrees (T) and 10 degrees (F). Make some more marks on the pulley or the crankcase to show you where 20 and 30 degrees are located.
I would put the marks on the pulley. I would advance the pulley until the notch is at the F and then I would put a mark on the pulley at the T (a red mark). I would then advance the pulley until the red mark is at the F and put a mark on the pulley at the T (a blue mark). I would then advance the pulley until the blue mark is at the F and put a mark on the pulley at the T (a green mark).
Using a timing light, verify the crank pulley is at the F mark when the engine is at idle and see where it is at 2000 and 3000 rpm. When the red mark is at the T, I have 10 degrees of advance. When the red mark is at the F, I have 20 degrees of advance. When the blue mark is at the T, I have 20 degrees of advance and when it is at the F, I have 30 degrees of advance. When the green mark is at the T, I have 30 degrees of advance.
I suspect your ignition timing is off which is causing the engine to not rev past 3K. The problem would be in the area of the distributor housing. It could be on the breaker plate, mechanical advance, or possibly the vacuum advance arm is preventing the breaker plate from rotating properly.
Other things could cause your problems but this is what I would be checking first. I have spent more time typing this message than it would have taken me to figure out your problem if I was looking at your car.
If you don't get the problem resolved, let us know more details such as;
1) did the car rev above 3K before you worked on it
2) What other checks have you done.....engine compression, valve adjustments, spark plug gap, does your timing light flash correctly when it is connected to either spark plug wire, are your brakes working and not dragging, have you worked on these cars before with success or is this your first Honda 600 car.
good luck,
Dale
> Hi everyone.
> Sedan stops reving at 3k rpm. As if it has a rev
> limiter. Feels like its running out of fuel - running lean.
> New plugs,
> coil, fuel pump, points.
> Starts great, idles great, runs great but
> when i hit 3k it bogs down as if its gonna die, with or without load, > misfire.
> Before I start working on carb/fuel and timing is there
> anybody else that had an issue similar to this?
> Thanks
> everyone.
Re: cant rev over 3k rpm
Good thoughts on all of it. But I would also look at the advancer assembly. A screw on the condenser too long can cause the system not to advance. A blocked exhaust can cause what seems like you have your brakes on all the time. But as the sign in my garage reads, "If all else fails READ THE INSTRUCTIONS and Follow Them!" Something is amiss.
Bill
Bill
-
promoter213
- Posts: 0
- Joined: Fri Mar 18, 2016 10:51 pm
Re: cant rev over 3k rpm
Thank You to everyone that replied with help to my problem.
Been busy but had the time to work on my car today.
Bryan, I checked for air leaks and there was none.
Bill, My advance assembly was not being obstructed but it did need cleaning as it was not smooth in transition. Cleaned it up but that did not solve problem but I was happy that I got a chance to clean it. Exhaust is flowing well.
Dale, I do not know if it rev'd over 3k before since there was no tach attached. I just recently decided to install one I had laying around which led me to this.
Engine compression is great. I did a valve adjustment back in March. Spark plugs are new and gapped to factory settings. Brakes are great, no dragging. First time working on n600 but been working on cars since my first car as a teen.
I also suspected timing (Thanks Dale) and it was off. Adjusted timing and now it runs great. Feels very responsive, more power and more fun!!
Im able to rev up to 4k rpm but after that the tach seems to jump/fluctuate, motor sounds like its still going but I rather not take the chance on how far I can take it. Does anybody else take it beyond 4k rpm? Im beyond the suggested gear vs speed at that point. Also getting some low rpm misfires. But other than that it runs far better than before. It actually feels fast, lol. I cant believe I was riding around with it under powered with the excuse of "it only has 35hp".
Thanks everyone for both listening and helping.
Been busy but had the time to work on my car today.
Bryan, I checked for air leaks and there was none.
Bill, My advance assembly was not being obstructed but it did need cleaning as it was not smooth in transition. Cleaned it up but that did not solve problem but I was happy that I got a chance to clean it. Exhaust is flowing well.
Dale, I do not know if it rev'd over 3k before since there was no tach attached. I just recently decided to install one I had laying around which led me to this.
Engine compression is great. I did a valve adjustment back in March. Spark plugs are new and gapped to factory settings. Brakes are great, no dragging. First time working on n600 but been working on cars since my first car as a teen.
I also suspected timing (Thanks Dale) and it was off. Adjusted timing and now it runs great. Feels very responsive, more power and more fun!!
Im able to rev up to 4k rpm but after that the tach seems to jump/fluctuate, motor sounds like its still going but I rather not take the chance on how far I can take it. Does anybody else take it beyond 4k rpm? Im beyond the suggested gear vs speed at that point. Also getting some low rpm misfires. But other than that it runs far better than before. It actually feels fast, lol. I cant believe I was riding around with it under powered with the excuse of "it only has 35hp".
Thanks everyone for both listening and helping.
Re: cant rev over 3k rpm
The red line on the USA Honda 600 engines was at 6,000 rpm. The engines would easily run beyond this number.
A restricted air inlet to the carb could cause the engine to not achieve a high rpm. Check the air filter, air cleaner box, and air horn. If you have a summer/winter bypass on the air horn, check it is clear in both directions. In the winter, the flap causes the engine to be heated by engine fan (1970 sedan) or by the exhaust heat exchanger (1971 & 1972 models).
The big clue to your current problem may be the misfire at low rpm.
That may be caused by high voltage arcing. I would look at the spark plug wires and connectors from the ignition coil to the plugs. Also, check where the ignition coil bolts to the car body. There is normally a ground cable at this point which attaches to the engine. This needs to be a clean connection. If you move the spark plug cable away from the body metal, you should be able to run a wire which is grounded to the car body along the length of the cable without drawing a spark (you could also use your finder or hand but this could prove to be painful if you get shocked).
Doing this spark test at night (in the dark) is usually helpful.
If the high voltage wiring looks ok, I would look at the timing again. The dwell angle on the engine is 90 degrees. My meter doesn't have a 2 cylinder setting and I have to make measurements at the 4 cylinder setting and double it (ie when it reads 45 degrees on my meter, it corresponds to 90 degrees). Also, look at advance versus rpm and see if it matches what is published in the sedan shop manual. The springs which are part of the mechanical advance on the breaker plate (in the distributor housing) get tempered by the engine temperature and lose their spring. When that happens, the breaker plate rotates too quickly with rpm and the ignition advances too much versus engine rpm.
good luck,
Dale
A restricted air inlet to the carb could cause the engine to not achieve a high rpm. Check the air filter, air cleaner box, and air horn. If you have a summer/winter bypass on the air horn, check it is clear in both directions. In the winter, the flap causes the engine to be heated by engine fan (1970 sedan) or by the exhaust heat exchanger (1971 & 1972 models).
The big clue to your current problem may be the misfire at low rpm.
That may be caused by high voltage arcing. I would look at the spark plug wires and connectors from the ignition coil to the plugs. Also, check where the ignition coil bolts to the car body. There is normally a ground cable at this point which attaches to the engine. This needs to be a clean connection. If you move the spark plug cable away from the body metal, you should be able to run a wire which is grounded to the car body along the length of the cable without drawing a spark (you could also use your finder or hand but this could prove to be painful if you get shocked).
Doing this spark test at night (in the dark) is usually helpful.
If the high voltage wiring looks ok, I would look at the timing again. The dwell angle on the engine is 90 degrees. My meter doesn't have a 2 cylinder setting and I have to make measurements at the 4 cylinder setting and double it (ie when it reads 45 degrees on my meter, it corresponds to 90 degrees). Also, look at advance versus rpm and see if it matches what is published in the sedan shop manual. The springs which are part of the mechanical advance on the breaker plate (in the distributor housing) get tempered by the engine temperature and lose their spring. When that happens, the breaker plate rotates too quickly with rpm and the ignition advances too much versus engine rpm.
good luck,
Dale
> Thank You to everyone that replied with help to my problem.
> Been
> busy but had the time to work on my car today.
> Bryan, I checked for air
> leaks and there was none.
> Bill, My advance assembly was not being
> obstructed but it did need cleaning as it was not smooth in transition.
> Cleaned it up but that did not solve problem but I was happy that I got a > chance to clean it. Exhaust is flowing well.
> Dale, I do not know
> if it rev'd over 3k before since there was no tach attached. I just recently > decided to install one I had laying around which led me to this.
> Engine
> compression is great. I did a valve adjustment back in March. Spark plugs are > new and gapped to factory settings. Brakes are great, no dragging. First time > working on n600 but been working on cars since my first car as a > teen.
> I also suspected timing (Thanks Dale) and it was off. Adjusted > timing and now it runs great. Feels very responsive, more power and more > fun!!
> Im able to rev up to 4k rpm but after that the tach seems to > jump/fluctuate, motor sounds like its still going but I rather not take the > chance on how far I can take it. Does anybody else take it beyond 4k rpm? Im > beyond the suggested gear vs speed at that point. Also getting some low rpm > misfires. But other than that it runs far better than before. It actually > feels fast, lol. I cant believe I was riding around with it under powered with > the excuse of "it only has 35hp".
> Thanks everyone for both listening
> and helping.
-
lloyd hays
- Posts: 0
- Joined: Tue Apr 05, 2016 7:03 am
Re: cant rev over 3k rpm
After 2weeks of trying everything under the sun for the exact same symptoms,I double checked the timing,it was 1 tooth off....I rolled the chain 1 tooth,and it ran excellent ever since!
On Thursday, May 12, 2016 1:50 PM, "goinhm@... [anzhonda600owners]" wrote:
I've seen that problem many times. From the few details you have offered, I could list 100 things which would cause your problem. You seem to be telling me that rev it at a standstill and it drops off at 3K and you can drive it and it drops off at 3K and it sounds perfect at idle (is that at 1050 rpm?). With that information, I would suspect you have an ignition or airflow problem.
For the airflow problem, remove the air filter and the cover plus check the choke is open when the engine is warmed up. Does it run above 3K rpm?
For the ignition problem, look at pg 2-12 of the sedan shop manual. You will see the engine advance for a n600/z600 is about 20 degrees at 3K rpm. The T and F timing marks on the crankcase correspond to 0 degrees (T) and 10 degrees (F). Make some more marks on the pulley or the crankcase to show you where 20 and 30 degrees are located.
I would put the marks on the pulley. I would advance the pulley until the notch is at the F and then I would put a mark on the pulley at the T (a red mark). I would then advance the pulley until the red mark is at the F and put a mark on the pulley at the T (a blue mark). I would then advance the pulley until the blue mark is at the F and put a mark on the pulley at the T (a green mark).
Using a timing light, verify the crank pulley is at the F mark when the engine is at idle and see where it is at 2000 and 3000 rpm. When the red mark is at the T, I have 10 degrees of advance. When the red mark is at the F, I have 20 degrees of advance. When the blue mark is at the T, I have 20 degrees of advance and when it is at the F, I have 30 degrees of advance. When the green mark is at the T, I have 30 degrees of advance.
I suspect your ignition timing is off which is causing the engine to not rev past 3K. The problem would be in the area of the distributor housing. It could be on the breaker plate, mechanical advance, or possibly the vacuum advance arm is preventing the breaker plate from rotating properly.
Other things could cause your problems but this is what I would be checking first. I have spent more time typing this message than it would have taken me to figure out your problem if I was looking at your car.
If you don't get the problem resolved, let us know more details such as;
1) did the car rev above 3K before you worked on it
2) What other checks have you done.....engine compression, valve adjustments, spark plug gap, does your timing light flash correctly when it is connected to either spark plug wire, are your brakes working and not dragging, have you worked on these cars before with success or is this your first Honda 600 car.
good luck,
Dale
On Thursday, May 12, 2016 1:50 PM, "goinhm@... [anzhonda600owners]" wrote:
I've seen that problem many times. From the few details you have offered, I could list 100 things which would cause your problem. You seem to be telling me that rev it at a standstill and it drops off at 3K and you can drive it and it drops off at 3K and it sounds perfect at idle (is that at 1050 rpm?). With that information, I would suspect you have an ignition or airflow problem.
For the airflow problem, remove the air filter and the cover plus check the choke is open when the engine is warmed up. Does it run above 3K rpm?
For the ignition problem, look at pg 2-12 of the sedan shop manual. You will see the engine advance for a n600/z600 is about 20 degrees at 3K rpm. The T and F timing marks on the crankcase correspond to 0 degrees (T) and 10 degrees (F). Make some more marks on the pulley or the crankcase to show you where 20 and 30 degrees are located.
I would put the marks on the pulley. I would advance the pulley until the notch is at the F and then I would put a mark on the pulley at the T (a red mark). I would then advance the pulley until the red mark is at the F and put a mark on the pulley at the T (a blue mark). I would then advance the pulley until the blue mark is at the F and put a mark on the pulley at the T (a green mark).
Using a timing light, verify the crank pulley is at the F mark when the engine is at idle and see where it is at 2000 and 3000 rpm. When the red mark is at the T, I have 10 degrees of advance. When the red mark is at the F, I have 20 degrees of advance. When the blue mark is at the T, I have 20 degrees of advance and when it is at the F, I have 30 degrees of advance. When the green mark is at the T, I have 30 degrees of advance.
I suspect your ignition timing is off which is causing the engine to not rev past 3K. The problem would be in the area of the distributor housing. It could be on the breaker plate, mechanical advance, or possibly the vacuum advance arm is preventing the breaker plate from rotating properly.
Other things could cause your problems but this is what I would be checking first. I have spent more time typing this message than it would have taken me to figure out your problem if I was looking at your car.
If you don't get the problem resolved, let us know more details such as;
1) did the car rev above 3K before you worked on it
2) What other checks have you done.....engine compression, valve adjustments, spark plug gap, does your timing light flash correctly when it is connected to either spark plug wire, are your brakes working and not dragging, have you worked on these cars before with success or is this your first Honda 600 car.
good luck,
Dale
> Hi everyone.
> Sedan stops reving at 3k rpm. As if it has a rev
> limiter. Feels like its running out of fuel - running lean.
> New plugs,
> coil, fuel pump, points.
> Starts great, idles great, runs great but
> when i hit 3k it bogs down as if its gonna die, with or without load, > misfire.
> Before I start working on carb/fuel and timing is there
> anybody else that had an issue similar to this?
> Thanks
> everyone.
Re: cant rev over 3k rpm
Better replace the timing chain!
Richard Sent from Yahoo Mail for iPhone
Richard Sent from Yahoo Mail for iPhone
On Wednesday, May 25, 2016, 4:05 PM, lloyd hays deerbut2000@... [anzhonda600owners] wrote:
> After 2weeks of trying everything under the sun for the exact same symptoms,I double checked the timing,it was 1 tooth off....I rolled the chain 1 tooth,and it ran excellent ever since!
> On Thursday, May 12, 2016 1:50 PM, "goinhm@... [anzhonda600owners]" wrote:
> I've seen that problem many times. From the few details you have > offered, I could list 100 things which would cause your problem. You > seem to be telling me that rev it at a standstill and it drops off at 3K and you > can drive it and it drops off at 3K and it sounds perfect at idle (is that at > 1050 rpm?). With that information, I would suspect you have an > ignition or airflow problem.
> For the airflow problem, remove the air filter and the cover plus > check the choke is open when the engine is warmed up. Does it run above 3K > rpm?
> For the ignition problem, look at pg 2-12 of the sedan shop > manual. You will see the engine advance for a n600/z600 is about 20 > degrees at 3K rpm. The T and F timing marks on the crankcase correspond to > 0 degrees (T) and 10 degrees (F). Make some more marks on the pulley > or the crankcase to show you where 20 and 30 degrees are located.
> I would put the marks on the pulley. I would advance the pulley until > the notch is at the F and then I would put a mark on the pulley at the T (a red > mark). I would then advance the pulley until the red mark is at > the F and put a mark on the pulley at the T (a blue mark). I would then > advance the pulley until the blue mark is at the F and put a mark on the pulley > at the T (a green mark).
> Using a timing light, verify the crank pulley is at
> the F mark when the engine is at idle and see where it is at 2000 > and 3000 rpm. When the red mark is at the T, I have 10 > degrees of advance. When the red mark is at the F, I have 20 degrees > of advance. When the blue mark is at the T, I have 20 degrees of > advance and when it is at the F, I have 30 degrees of advance. When > the green mark is at the T, I have 30 degrees of advance.
> I suspect your ignition timing is off which is causing the engine to not > rev past 3K. The problem would be in the area of the distributor > housing. It could be on the breaker plate, mechanical advance, > or possibly the vacuum advance arm is preventing the breaker plate from rotating > properly.
> Other things could cause your problems but this is what I would be checking > first. I have spent more time typing this message than it would have > taken me to figure out your problem if I was looking at your car.
> If you don't get the problem resolved, let us know more details such > as;
> 1) did the car rev above 3K before you worked on it
> 2) What other checks have you done.....engine compression, > valve adjustments, spark plug gap, does your timing light flash > correctly when it is connected to either spark plug wire, are your > brakes working and not dragging, have you worked on these cars before with > success or is this your first Honda 600 car.
> good luck,
> Dale
> > Hi everyone.
> > Sedan stops reving at 3k rpm. As if it has a rev
> > limiter. Feels like its running out of fuel - running lean.
> > New plugs,
> > coil, fuel pump, points.
> > Starts great, idles great, runs great but
> > when i hit 3k it bogs down as if its gonna die, with or without load, > > misfire.
> > Before I start working on carb/fuel and timing is there
> > anybody else that had an issue similar to this?
> > Thanks
> > everyone.
-
Bart Schile
- Posts: 0
- Joined: Sun Dec 11, 2011 9:36 am
Re: cant rev over 3k rpm
I would replace the tensioner also
Re: cant rev over 3k rpm
The hydraulic tensioner has been known to get plugged over time and no longer operate as it should. The O rings get hard as a rock but if the oil is changed often there shouldn’t be a problem. But it is one reason the cam chain could be loose. There are several things to look at, wear between the teeth in the cam and crankshaft, the cam chain can stretch and the tensioner no longer performing as it should. Nothing to joke about but if the timing mark on the pulley goes to the “F” on the housing then your cam chain finished.
See the test below. But as Dale has already said, there are a few things to look at.
The test is really simple, With the engine off, (Remove the oil fill cap) using a flash light move the crank shaft until the timing notch on the cam is centered in the cam bearing notch. Then look at the notch on the timing pulley, it should be on the "T". Now move the pulley back toward the "F" mark on the same housing as the "T" mark. The cam notch should move the same distance as the pulley notch. If it doesn't, measure the distance from the "T" mark to where the cam starts to move. Add that to one and one sixteenth inches and you will know how much your cam chain has stretched.
Bill
See the test below. But as Dale has already said, there are a few things to look at.
The test is really simple, With the engine off, (Remove the oil fill cap) using a flash light move the crank shaft until the timing notch on the cam is centered in the cam bearing notch. Then look at the notch on the timing pulley, it should be on the "T". Now move the pulley back toward the "F" mark on the same housing as the "T" mark. The cam notch should move the same distance as the pulley notch. If it doesn't, measure the distance from the "T" mark to where the cam starts to move. Add that to one and one sixteenth inches and you will know how much your cam chain has stretched.
Bill