Hi all,
Getting a massive 22mpg out of the Z. I do not know where the problem
is. When I time the engine, the light is firing right on the f mark.
I have the plugs at correct gap, I have the carb idle screw at the
correct 1.25 turns out from stop, and I have filed and reset the points
to the correct gap. The car seems to be lacking a little power, but
otherwise is running and starting good.
Any ideas?
Kc
Poor Gas Mileage Questions
Re: Poor Gas Mileage Questions
Hi KC,
Here are some things to check;
1) Is the air filter clean?
2) Any leaks at the intake (at the "rubber" boot which attaches the carb to the intake)?
3) How is the compression in each cylinder? Is it about 160 psi per cylinder?
4) Is this something which happened recently? If not, check position of your cam .... if the timing is off, the fuel economy and performance will suffer. Also, check your valve clearance while in the cam area.
5) You may have a problem with your carb.... the float level could be off, the valve seat may be leaking (the needle and seat which is actuated by the float).
6) If you live in a state where air quality emissions are performed on the car, you could take it in for readings and that may give you some insight into the problem.
7) filing the points doesn't always make the points good again.
You really need to check the resistance and ensure that it is low (less than 50 milliohms) and stays low with each contact. If it jumps around between low and high readings, your points are not behaving correctly. A high reading would be anything above 0.5 ohms.
8) have you replaced the spark plugs with new ones?
9) any arcing of the high voltage section? You should be able to run your hand along the entire length of each ignition wire from the coil to near the plug without being shocked. If you do this, be careful since the high voltage can bite. You might try keeping one hand in a pocket or grounding the wrist of the hand doing the probing to the chassis of the car ..... you are trying to avoid an electrical path which travels from one hand, across the chest, to the other hand and then to ground.
good luck,
Dale
Here are some things to check;
1) Is the air filter clean?
2) Any leaks at the intake (at the "rubber" boot which attaches the carb to the intake)?
3) How is the compression in each cylinder? Is it about 160 psi per cylinder?
4) Is this something which happened recently? If not, check position of your cam .... if the timing is off, the fuel economy and performance will suffer. Also, check your valve clearance while in the cam area.
5) You may have a problem with your carb.... the float level could be off, the valve seat may be leaking (the needle and seat which is actuated by the float).
6) If you live in a state where air quality emissions are performed on the car, you could take it in for readings and that may give you some insight into the problem.
7) filing the points doesn't always make the points good again.
You really need to check the resistance and ensure that it is low (less than 50 milliohms) and stays low with each contact. If it jumps around between low and high readings, your points are not behaving correctly. A high reading would be anything above 0.5 ohms.
8) have you replaced the spark plugs with new ones?
9) any arcing of the high voltage section? You should be able to run your hand along the entire length of each ignition wire from the coil to near the plug without being shocked. If you do this, be careful since the high voltage can bite. You might try keeping one hand in a pocket or grounding the wrist of the hand doing the probing to the chassis of the car ..... you are trying to avoid an electrical path which travels from one hand, across the chest, to the other hand and then to ground.
good luck,
Dale
See what's new at AOL.com and Make AOL Your Homepage .> Getting a massive 22mpg out of the Z. I do not know where the problem
> is. When I time the engine, the light is firing right on the f mark.
> I
> have the plugs at correct gap, I have the carb idle screw at the > correct > 1.25 turns out from stop, and I have filed and reset the points > to the > correct gap. The car seems to be lacking a little power, but > otherwise is > running and starting good.
Re: Poor Gas Mileage Questions
Hi,
I believe that I am having point jump at all RPM's I think that the
spring has sprung at the points. When I time the engine with a timming
light off of the flywheel, 85% of the time the light is showing the
grove at the "f" mark. the other 15% of the time the mark is about
1/8" toward the "t" mark (at 1200 RPM idle)! Is this common. If I do
have a problem with the points, How can I get new ones? Anyone got a #?
Thanks,
KCandtheZ
I believe that I am having point jump at all RPM's I think that the
spring has sprung at the points. When I time the engine with a timming
light off of the flywheel, 85% of the time the light is showing the
grove at the "f" mark. the other 15% of the time the mark is about
1/8" toward the "t" mark (at 1200 RPM idle)! Is this common. If I do
have a problem with the points, How can I get new ones? Anyone got a #?
Thanks,
KCandtheZ
-
tommyjayallen
- Posts: 1
- Joined: Wed Oct 12, 2016 2:26 am
Re: Poor Gas Mileage Questions
You need to set your idle lower. At 1200 RPM you are already in the advance curve. I think the idle should be around 900. Make sure you have the Vaccum line disconnected and plugged. when you set the timing. Good luck.
kcandthez wrote:
kcandthez wrote:
> Hi,
> I believe that I am having point jump at all RPM's I think that the > spring has sprung at the points. When I time the engine with a timming > light off of the flywheel, 85% of the time the light is showing the > grove at the "f" mark. the other 15% of the time the mark is about > 1/8" > toward the "t" mark (at 1200 RPM idle)! Is this common. If I do > have a problem with the points, How can I get new ones? Anyone got a #?
> Thanks,
> KCandtheZ
Be a better sports nut! Let your teams follow you
with Yahoo Mobile.
Try it now.
Re: Poor Gas Mileage Questions
I thought it was high, but the manual I have says between 1100 rpm and
1200 idle. I cannot get the car to idle well under 1k rpm.
I'll do a compression test on the engine, but It has new rings and I
seem to not be getting blow by or burning oil. I believe that the
points are worn beyond use. The spark advance is working, and I have
rebuilt the coil. I enstalled new plugs NGK's. and all seems well.
I need to get this to a motorcycle place I believe, it is annoying.
I am going full steam with the electronic ignition for the Z. I have
found what I believe will work, just have to check some measurements
and check with the manufacturer to see if they will fit in the housing.
KCandtheZ
1200 idle. I cannot get the car to idle well under 1k rpm.
I'll do a compression test on the engine, but It has new rings and I
seem to not be getting blow by or burning oil. I believe that the
points are worn beyond use. The spark advance is working, and I have
rebuilt the coil. I enstalled new plugs NGK's. and all seems well.
I need to get this to a motorcycle place I believe, it is annoying.
I am going full steam with the electronic ignition for the Z. I have
found what I believe will work, just have to check some measurements
and check with the manufacturer to see if they will fit in the housing.
KCandtheZ
Re: Poor Gas Mileage Questions
The Honda Sedan shop manual mentions an idle speed of 1100 to 1200 for the sedan. The coupe shop manual mentions an idle speed of 1100 to 1200 rpm. Selecting 1100 rpm will use less fuel at idle if the car will idle smoothly and without hesitation.
good luck,
Dale
good luck,
Dale
See what's new at AOL.com and Make AOL Your Homepage .> I thought it was high, but the manual I have says between 1100 rpm and
> 1200 idle. I cannot get the car to idle well under 1k rpm.
> I'll do a
> compression test on the engine, but It has new rings and I > seem to not be > getting blow by or burning oil. I believe that the