Still no power.

[Unsung]

'77 CJ7 , 232i6, T-18 4spd, 3.54 gears, 36inch tires. Stock motor, rebuilt a few years ago but barely run, MSD ignition.

Tops out at 45mph. I've adjusted the timing everywhere, checked compression, put small tires on it. Nothing makes it move any faster. It tops out at 45, takes a long time to get there, and won't spin the tires in gravel even with the granny first.

 

[Hedgehog]

3.54 gears and 36" tires ...... oh my!

 

[Jimbos76cj]

'77 CJ7 , 232i6, T-18 4spd, 3.54 gears, 36inch tires. Stock motor, rebuilt a few years ago but barely run, MSD ignition.

Tops out at 45mph. I've adjusted the timing everywhere, checked compression, put small tires on it. Nothing makes it move any faster. It tops out at 45, takes a long time to get there, and won't spin the tires in gravel even with the granny first.

How are you clocking your speed? If you still have the stock speedo gear and its showing 45 your actually closer to 55-60

how small were the tires you put on it?

Whats your timing at? How are you shifting? Really with 36" tires on 3;55 gears you wont be able to spin the tires and haul ***. with 36" tires and 3:55 gears you should be turning around 2200 rpm. Its a jeep not a race car.. Id suggest you look into 4:88 gears.

 

[Fastatv]

Have you checked to see if your timing is actually advancing? Another idea, could you have a dragging brake issue? My 76 had a couple brakes dragging badly, once I freed them up, big difference in power.

 

[Unsung]

Speed checked by another car following me. I said I put smaller tires, they were 31x10.5. No tach so I can't tell you what rpm I am shifting at, but I'd guess about 2,500. Sometimes more just trying to get the thing to move faster. Brakes aren't dragging, I can push the jeep by hand. Even with the advance not working, I would expect to get over 45mph on 31inch tires with a rebuilt engine, and also I just put this ignition system and new distributor in it because I thought the stock one might be the problem, so unless I have the advance vacuum hose plugged into the wrong hole..

I wonder about exhaust being stopped up, or maybe something in the drivetrain slipping?

 

[Fastatv]

Might be a good idea to ensure the vacuum advance is hooked up correctly. Should be a "delayed port" from the carb. No vacuum at idle, but as soon as throttle is cracked, will have vacuum. Could also be a leaky advance diaphragm. How well does it rev when in neutral?

 

[Scooter402]

Speed checked by another car following me. I said I put smaller tires, they were 31x10.5. No tach so I can't tell you what rpm I am shifting at, but I'd guess about 2,500. Sometimes more just trying to get the thing to move faster. Brakes aren't dragging, I can push the jeep by hand. Even with the advance not working, I would expect to get over 45mph on 31inch tires with a rebuilt engine, and also I just put this ignition system and new distributor in it because I thought the stock one might be the problem, so unless I have the advance vacuum hose plugged into the wrong hole..

I wonder about exhaust being stopped up, or maybe something in the drivetrain slipping?

You may be onto something there.

 

[Unsung]

Might be a good idea to ensure the vacuum advance is hooked up correctly. Should be a "delayed port" from the carb. No vacuum at idle, but as soon as throttle is cracked, will have vacuum. Could also be a leaky advance diaphragm. How well does it rev when in neutral?

Yeah there's no vacuum port in the side of the motor anymore. The vacuum line is plugged into the carburetor. Wouldn't a non-functioning vacuum advance only effect the top end power? It has neither top or bottom end.

 

[Fastatv]

Yeah there's no vacuum port in the side of the motor anymore. The vacuum line is plugged into the carburetor. Wouldn't a non-functioning vacuum advance only effect the top end power? It has neither top or bottom end.

Does it rev good in neutral? Your carb should have a "delayed spark" port somewhere on it to attach the vacuum advance. Normally the vacuum advance is not connected on the engine. The advance begins as soon as the throttle is slightly cracked open......will def affect bottem end power. There are also springs and weights in the distributor, as the distributor rotates faster, the timing is also advanced. Have you put a timing light on it to verify initial timing, and that your advance is working? Are you sure that the distributor is installed correctly.....could be off a tooth off.

 

[Unsung]

Does it rev good in neutral? Your carb should have a "delayed spark" port somewhere on it to attach the vacuum advance. Normally the vacuum advance is not connected on the engine. The advance begins as soon as the throttle is slightly cracked open......will def affect bottem end power. There are also springs and weights in the distributor, as the distributor rotates faster, the timing is also advanced. Have you put a timing light on it to verify initial timing, and that your advance is working? Are you sure that the distributor is installed correctly.....could be off a tooth off.

It revs good, idles good. All in all the thing runs fantastic. Starts easy without giving it gas. I step on the pedal to choke it and that's it, just no power. I looked all over google trying to find where the vacuum hose should go on the carburetor with no luck.

 

[hagar]

3.54 gears and 36" tires ...... oh my!

and a AMC 232 i6 ......

yep

 

[Barry2]

Make sure you're getting full throttle and check for a plugged up exhaust system.

 

[Unsung]

and a AMC 232 i6 ......

yep

Will a AMC 232 i6 run over 45mph with 3.54 gears and 31" tires? I believe so. In fact larger tires doesn't limit your top speed THAT significantly. It mostly just makes it where it takes a bit longer to get up to speed. So yeah I know.

 

[Jimbos76cj]

Will a AMC 232 i6 run over 45mph with 3.54 gears and 31" tires? I believe so. In fact larger tires doesn't limit your top speed THAT significantly. It mostly just makes it where it takes a bit longer to get up to speed. So yeah I know.

Its not just the size of the wheel but the added unsprung weight that it adds.. I think you have an issue somplace but since you know i will no longe add suggestions.

 

[Shifter]

Have a vacuum guage ?

What is your manifold vacuum at idle ??

Is the needle smooth or jumpy??

 

[NorthwestCJer]

Excellent question above from "Shifter".
I am leaning towards vac advance problem first. Vac advance only works under 1800 rpm. It is for power in acceleration.

What are you timing it at?. 6?8?12? what?

Are you using a dwell/tach meter so you know what your idle is set at?

Did you plug off the vac advance before timing the engine?

I believe you said you replaced the dist. was there issues? did the new one line up exactly like the old one when you were done?

You said MSD ignition? just a coil or what are you running now for dist. reason I am asking is that this AMC 232 i6 probably had points originally and if all you did is put a coil on it. Good chance you haven't set your points.

Lets see pics of your setup??

 

[jdarg]

IMHO this is a no-brainer...way too much tire for your current engine/gear combo.

Prove it to yourself - find a smaller set of tires to put on there and take it for a short drive.

 

[NorthwestCJer]

IMHO this is a no-brainer...way too much tire for your current engine/gear combo.

Prove it to yourself - find a smaller set of tires to put on there and take it for a short drive.

If you will read back threw this thread. You will see he already stated he mounted a set of 31's to try it. This is why questions are being asked.