Engine timing problems

[Bob_Spidell]

It's a long shot, but are you sure there is no blockage in the exhaust system?

 

[Jeepster]

Update 2 -

set ignition with both points and elec ign installed. Still didn't want to run over 2000rpm.

Decided that the fault was not with the ignition or the fuel delivery so set to work on the carbs.

Finally found the fault was with the rear carbs diaphram/jet. It was seized and wouldn't allow any adjustment. We finally managed to force it to a setting that matched the front carb and the cars performance was restored.

I have just ordered a pair of jets and needles and when these are fitted the carbs can be tuned and hopefully problem solved.

many thanks for your help with this one.

 

[John Turney]

Excellent! Thanks for getting back with the result.

 

[RAC68]

Great to hear.

However, I am a little confused. Am I correct in understanding that this condition started on your 100 mile trip and, since I wouldn't expect you to leave on such a long trip without having the car in good order, that the engine ran well prior and during some portion of the trip? If so, do you know what condition happened to have caused the needle to jam (i.e. something broke, something in the fuel, etc.). I am asking because this is condition is not common and would have never entered my thoughts unless there was something overtly pointing to this condition.

Again, happy to hear you have discovered the cause.

All the best,
Ray (64BJ8P1)

 

[Jeepster]

Great to hear.

However, I am a little confused. Am I correct in understanding that this condition started on your 100 mile trip and, since I wouldn't expect you to leave on such a long trip without having the car in good order, that the engine ran well prior and during some portion of the trip? If so, do you know what condition happened to have caused the needle to jam (i.e. something broke, something in the fuel, etc.). I am asking because this is condition is not common and would have never entered my thoughts unless there was something overtly pointing to this condition.

Again, happy to hear you have discovered the cause.

All the best,
Ray (64BJ8P1)

It confused me too. The engine has run fine for years and was fine before I started on my 100 mile trip. It wasn't the needle that jammed but the jet. My mechanic took off the dash pots and noticed the jet adjustment was not matched between the two carbs. When he tried to adjust the jet on the rear carb it was jammed solid. As it was to be replaced anyway, he tried to budge it with a small socket to match the front carb. As soon as the two were matched the problem disappeared and the car revved easily over 2000 revs. A new set of jets and needles are on order and will be fitted next week and the carbs tuned.
I always seem to get the complicated faults. No idea why the engine ran fine for so long and then all of a sudden started to cause problems? It must have been running too lean from one of the carbs?

 

[steveg]

Finally found the fault was with the rear carbs diaphram/jet. It was seized and wouldn't allow any adjustment. We finally managed to force it to a setting that matched the front carb and the cars performance was restored.

I had this exact problem twice with a brass replacement jet from one of our favorite suppliers. I removed the jet diaphragm and sanded the peripery down a little with wet-dry paper until it slid easily in the housing. Then after a few months it seemed to "grow" and seized again. Sanded it some more. That was maybe 3 years ago - it's been working fine ever since.

 

[Jeepster]

The saga continues.

As per my last post -

after much fiddling, with the help of my local mechanic I manged to set the carbs up and the engine was much improved.
Went for a few small drives and all seemed ok.

then just as I returned home after a short trip, the engine seemed lumpy at tickover and wanted to stall. I had to keep the engine running at tickover with the accelerator pedal.
The engine now struggles to start and is really lumpy at low revs ( 2000 ish). Over 2000 revs the engine is smooth.

Decided I needed to try and re tune the carbs so started to follow Steve Buyers instructions.

All the carb adjusting screws are set as recommended but the car will hardly start. If I do get it to start it won't stay running for more than a few seconds to allow the adjustments. Likewise I can't re check the timing as it won't run.
There is no chance of getting it running any where near the 500 rpm suggested.
I have adjusted the slow run screw in either direction with the hope that will assist with th initial set up but no joy.
Any ideas as its driving me nuts. I can't believe this is turning into a real pain in the bum.

 

[Keoke]

Hmm.

What is the fuel pump doing while all this baffling behavior is going on??

 

[Jeepster]

Hmm.

What is the fuel pump doing while all this baffling behavior is going on??

Fuel pump seems fine.

It clicks when ignition is turned on until system is primed and I have checked the fuel flow by disconnecting the hose that fees the carbs and putting the end in a container to see how much petrol is delivered. Also a filter before the pump.

 

[Keoke]

Fuel pump seems fine.

OK !:

Put it up on E Bay UK and add an additional 20,000 GBP because it has a problem no body in the world can figure out.

 

[Andy65]

If at some time you pulled the choke, the jet may be stuck again. Or the choke springs can't pull it down. Also, when I set the carbs with the main jet initially at 2 1/2 turns in from top of bridge, it wouldn't run. Turn both jets in 1/2 turn clockwise. Try it, then another 1/2 turn.

 

[Jeepster]

Fuel pump seems fine.

OK !:

Put it up on E Bay UK and add an additional 20,000 GBP because it has a problem no body in the world can figure out.

you may joke but its getting close to me doing that.

I have just gone over everything as per instructions. Jets set and air mix screws set. Fast idle screws backed off.
The car really does not want to start. When it does I have to sit in the car to try and keep the engine running.

a couple of questions -

I have needles with a groove rather than a shoulder at the top. Which part of the groove should line up with the piston edge? The side nearer the point or top of needle? When I look online I get conflicting info.

Should the fast run screws be backed off at the start of the tuning process? How can the engine tick over if these are off? Does the air screw take care of this? Again conflicting info online.

Unless I can get the car running at idle ( at any rpm) I am unable to move forward.

 

[Keoke]

I have needles with a groove rather than a shoulder at the top. Which part of the groove should line up with the piston edge?

The side nearer the point or top of needle? ------YES

Should the fast run screws be backed off at the start of the tuning procedure.----NO!!

Screw them in and then adjust them for the correct tick over after the engine warms up

 

[Andy65]

The mixture is way off. You are trying to get it to run at slow idle per the book procedure but the jet is too far off. It is not going to start at tick over. Our objective now is to find a mixture to just get it running. To do this, we need to find a jet setting that allows it to run. So you have to ignore initial settings which set the mixture at the extreme rich and get it to run at high idle then with the jet right then work on slow idle. Try exactly the following: 1. choke springs checked, lever right position. 2. slow run screw try 2 1/4 turns out, 3. jet to top of bridge then 2 1/2 turns which is probably too lean for your car and where the problem is. 4. fast idle engaged, screw touching plus a couple turns. We are bypassing the low idle. 5. Try it. probably won't run. 6. jet screw in another 1/4 turn - try again maybe sputter; 7. jet another 1/4 turn and try again, 8. another 1/4 and varoom it will start. Idle will be way off but it is running. Then work on the idle. Hope temps are not too cold that it needs lots of choke. Tip: A vacuum leak can cause problems. Check the intake manifold and carb bolts are tight. Don't ask how I know.
I don't know about the needles facing with groove but if it ran before, put it back the same way. If the pistons are going down and seating and not sticking, the groove direction is acceptable for now.
I had the same problem myself recently and the above got it running. Report back.

 

[Jeepster]

Andy,

thanks for the suggestion,

i have followed your directions and set the fast idle screws in to assist with tickover. The engine turns over for a good few seconds before it struggles to fire. This happens all the way through the jet adjustment. I managed to to do a total of 8 quarter turns. The best I had was the engine struggles to fire and then ran steady at 2000 rpm. As I got round to the front of the car to try and back off the fast idle, the engine died. It must have run for 40 - 60 seconds.
Every time I get the car started, the same thing happens. That is it runs at a high rpm but without me adjusting anything it eventually stops. It can run for anything up to a minute. Almost as if its running out of fuel?
Float bowls are set and full with petrol, pump works ok?

The quarter turns didn't seem to improve anything, especially the starting. Should I try to more of an adjustment as they must be pretty low by now. Can the mixture being off cause that stopping after a minute?

 

[Jeepster]

Just tried moving the jets all across their adjustment range from almost flush with the bridge to as far down as they go
( about 5 mm). Tried to start the car at every adjustment and pretty much the same issue. Difficult to start and then runs for anywhere from 20 to 60 seconds before it dies. The fast idle screws are still set to run at about 2000 rpm.

New jets, new needles, new ignition, new fuel pump, new fuel tank.
Maybe it's time for a new owner?

 

[Keith_M]

This is starting to sound like an electrical problem. If the float bowls are full and the jets set rich, the car should run unless there's an enormous vacuum leak (have you checked that? Check all the nuts on the intake manifold and carbs.) I think I would be replacing points, condenser, rotor, and cap at this point.

 

[Keoke]

Jeepster

Is there any chance you have gotten water in the petro???

 

[Jeepster]

This is starting to sound like an electrical problem. If the float bowls are full and the jets set rich, the car should run unless there's an enormous vacuum leak (have you checked that? Check all the nuts on the intake manifold and carbs.) I think I would be replacing points, condenser, rotor, and cap at this point.

I have been having problems for the past few months. ALL ignition items have been replaced with new. Plugs, points, leads, cap, rotor, condenser.
Checked for a leak and re checked the carb bolts.

 

[Jeepster]

Jeepster

Is there any chance you have gotten water in the petro???

well we do have a lot of water here in Wales but the fuel was fresh from the pump a week or so back. I do wonder what quality of fuel we buy sometimes though.