Jeep not starting now...Now running

[moonus]

Hi all.
This is my first post on here, so please be gentle with me if I’ve not completely followed the correct protocol. I've posed this on the Hotchkiss section of the forum but didn't get a reply, so may be you MB guys can help as the engine is the same.

I’m having an issue with my Hotchkiss not starting. So I think the best place to start is with a bit of history first.

When I first got the jeep it was running OK. After bring the jeep home on a car transporter, I drove it for about 10 miles and then put it away in the garage. It was always my intension to renovate it first before using it, as I didn’t know the full jeep’s history and wanted to make sure things such as engine oil, diff oil, etc were good first. So like most things life got in the way, and what was going to take a couple of month’s turns into 3 years of renovating the jeep.

The work I’ve carried out in that time has all been on the chassis, such as new road springs, shackles, break shoes, bearings, bodywork and so on. Now all that’s done, I’ve now tuned my attention to the engine.
I didn’t want to do too much in one go, so I changed as little as possible so if there was an issue when restarting it, then not too much would have been changed from when I put it away. Hopefully making fault finding easier.
Before I stated any work on the jeep, I wanted to make sure the engine was in good shape first, so the first thing I did was a compression test and the results were.
1 piston 105psi
2 piston 95psi
3 piston 95psi
4 piston 105psi
I also wanted to check the valve clearance, but I’m having an issue with the timing marks not lining up in the window with piston 1 at TDC. It looks to me that the fly wheel is 180-deg out?

I know that the previous owner adjusted the ignition timing by a number of degs, this was to allow for unleaded fuel to be used with the original valve seats in. I want to put this back to its original setting and use fuel additive, but left is as it was for now as I want to get the engine running first.
The distributer is the original sealed type with the coil enclosed inside. All the watertight HT leads were replaced (not by me) with normal type of HT leads and caps. These leads just had the copper core splade back and then pushed down into the top of the distributer, this is not the best solution, but as it was working when I got the jeep I’ve left them as they are for now.

The engine parts that have been rebuilt are as follows:
1. PVC valve
2. Heat valve assemble (mounted below the carb)
3. Cooling water thermostat (new one fitted)
4. Ignition switch contacts cleaned & tested.
5. Solex carb rebuilt with carb kit.
6. Fuel pump rebuilt with pump kit.

Before trying to starting the jeep a few days ago, an aux fuel tank (the bottle type used for motorbikes) was rigged up to the fuel filter. This was because the original fuel tank was found to be leaking. The carb was fitted and the fuel lines bleed/flushed using the fuel pump priming leaver. With the carb connected, choke fully out (accelerator pedal left well alone) I went for the first start, the engine turned over fine, but showed no sign of starting. There was no hint of it trying to fire up, but there was a strong smell of fuel. I did find fuel seeping out from the seals around the butterfly shaft on the carb, even though these were replace with new seals.
After removing the carb, looking down into the inlet manifold I found it to be full of fuel. I rechecked the seals on the carb and all looked to be fine. I tested the float needle to make sure it was shutting the fuel supply off, this was working correctly.
I refitted the carb, but reading a number of forums found that the Solex can be sensitive to the fuel inlet pressure. With this in mind, I’ve lowered the position of the aux tank down to the same level of the original tank so as to reduce the head pressure. I fitted spark plugs testers to each plug and can see a good strong spark on each plug when cranking. This time when trying to start, there was far less fuel leaking around the carb seals, and although it didn’t start, this time it would back fire through the carb after about 3-4 seconds of cranking. The air filter isn’t fitted, but I shouldn’t think this should make much difference?

So a few questions that may be someone can answer:
1. On these engines, is no 1 piston at the water pump end?
2. Is piston no 1 on the distributer cap located at approx. 5 – 5:30 position?
3. Is it possible for the flywheel to be fitted 180-deg out?
4. Is it worth getting the carb rebuilt for £200 or get another Solex?

Any ideas or suggestions will be much welcome, as I’ve run out of them.

Cheers Roy.

[artificer]

Updated in a later post....

[cjv-35]

I was under the assumption that compression is best checked with engine at OPPERATING temp. Am I wrong ?

[artificer]

I was under the assumption that compression is best checked with engine at OPERATING temp. Correct.
Roy just got through telling us the engine was not starting, so a reasonable assumption would be that the test was done when the engine was cold.

[moonus]

Thanks for your replies guys.

If as stated, rebuilt I would be checking the excess fuel setup is correctly fitted & the plates are sealing.
Not sure what you are referring to here?

I ordered a standard seal kit for the fuel pump, not sure what spring force was supplied with the kit.
Today I tried to test if the pump was part of the issue. Not having a suitable pressure gauge/hose/fittings I disconnect the fuel line between the pump and the carb and connected the aux fuel tank directly to the carb inlet. I then tried starting the engine and at different intervals changed the height of the tank to try and give a range of head pressure. The engine still wouldn’t start and there was still the strong smell of fuel, although there was no fuel seeping from the butterfly shaft seals. I’ve also tried rotating the distributer through its full travel whist cranking, but there was still no sign of the engine wanting to start.

[moonus]

I was under the assumption that compression is best checked with engine at OPERATING temp. Correct.
Roy just got through telling us the engine was not starting, so a reasonable assumption would be that the test was done when the engine was cold.

Sorry yes I should have said that the test was done with a could engine, and these results were done when I first got the jeep, 3 years ago. I was going to do another compression test, as I was thinking the problem could be down to a valve stuck open, but the way the engine sound when cranking it would have to be number of valves stuck open and I find that hard to believe. Obviously another retest would have to be done with a cold engine as it wont start, but it would show if a valve was not sealing properly.

[artificer]

1 piston 105 psi 2 piston 95 psi 3 piston 95 psi 4 piston 105 psi
Pretty good for a cold engine
Something you should be doing again as this was done years ago apparently. Backfiring can be sticking/stuck valves & this is a real possibility with a long standing unused L134

I also wanted to check the valve clearance, but I’m having an issue with the timing marks not lining up in the window with piston 1 at TDC. It looks to me that the flywheel is 180-deg out?
If there....because some flywheels are not marked & visible, the marks will be lining up when 2&3 are @ TDC, though.
This method of tappet adjustment with or without feeler gauges may help:
http://jeepdraw.com/images/ADJUSTING-TA ... IBBINS.pdf
With the side cover off it is very EZ to see if any valves are stuck open.

So a few questions that may be someone can answer:
1. On these engines, is no 1 piston at the water pump end?
Yes
2. Is piston no 1 on the distributer cap located at approx. 5 – 5:30 position?
Usually, but depending on what has been done over time, not always
http://www.1942mb.com/article/5/G503-WW ... ne-Tune-Up
3. Is it possible for the flywheel to be fitted 180-deg out?
Yes If marked
4. Is it worth getting the carb rebuilt for £200 or get another Solex?
NO. Because no one knows what the problem is & whatever it is may be easily fixed & quite possibly not the carburettor @ all
If as stated, rebuilt I would be checking the excess fuel setup is correctly fitted & the plates are sealing.
If you have had the carburettor apart you will see part 64 the starter valve assy.
http://www.m201.com/tech/solex.htm
This & where this plate mates must not be scored or damaged. This mechanism allows excess fuel for starting.
What happens after your compression is retested, the timing is set properly & you try to start without any choke & that is the wrong descriptor i.e. any excess fuel because the cable is pulled out? Spark plugs won't fire if over wet with fuel. Also when suspected flooding the accelerator pedal should be floored when trying to start to get more air & less fuel.
What strength diaphragm spring was fitted to the fuel pump when re-building [this spring controls fuel pump pressure & is critical].
What pressure is being put out now?

You say you have good spark & backfiring occasionally when trying to start plus flooding.
Understand what flooding can be caused by & eliminate all possibilities.
This is what diagnosis [& not guessing] is all about.
1. Needle not seating properly. This needle is usually caged & the slightest contaminant, especially thread tape & the like, can cause not seating properly.
2. Float level too high.
3. Perforated or leaking float filling with fuel.
4. Overpressured & possible because apparently many current kits [meant to fit multiple vehicles] do not come with the right spring for the WW2 Jeep engine. Use your old spring.

[moonus]

1 piston 105 psi 2 piston 95 psi 3 piston 95 psi 4 piston 105 psi
Pretty good for a cold engine
Something you should be doing again as this was done years ago apparently. Backfiring can be sticking/stuck valves & this is a real possibility with a long standing unused L134

I also wanted to check the valve clearance, but I’m having an issue with the timing marks not lining up in the window with piston 1 at TDC. It looks to me that the flywheel is 180-deg out?
If there....because some flywheels are not marked & visible, the marks will be lining up when 2&3 are @ TDC, though.
This method of tappet adjustment with or without feeler gauges may help:
http://jeepdraw.com/images/ADJUSTING-TA ... IBBINS.pdf
With the side cover off it is very EZ to see if any valves are stuck open.

So a few questions that may be someone can answer:
1. On these engines, is no 1 piston at the water pump end?
Yes
2. Is piston no 1 on the distributer cap located at approx. 5 – 5:30 position?
Usually, but depending on what has been done over time, not always
http://www.1942mb.com/article/5/G503-WW ... ne-Tune-Up
3. Is it possible for the flywheel to be fitted 180-deg out?
Yes If marked
4. Is it worth getting the carb rebuilt for £200 or get another Solex?
NO. Because no one knows what the problem is & whatever it is may be easily fixed & quite possibly not the carburettor @ all
If as stated, rebuilt I would be checking the excess fuel setup is correctly fitted & the plates are sealing.
If you have had the carburettor apart you will see part 64 the starter valve assy.
http://www.m201.com/tech/solex.htm
This & where this plate mates must not be scored or damaged. This mechanism allows excess fuel for starting.
What happens after your compression is retested, the timing is set properly & you try to start without any choke & that is the wrong descriptor i.e. any excess fuel because the cable is pulled out? Spark plugs won't fire if over wet with fuel. Also when suspected flooding the accelerator pedal should be floored when trying to start to get more air & less fuel.
What strength diaphragm spring was fitted to the fuel pump when re-building [this spring controls fuel pump pressure & is critical].
What pressure is being put out now?

You say you have good spark & backfiring occasionally when trying to start plus flooding.
Understand what flooding can be caused by & eliminate all possibilities.
This is what diagnosis [& not guessing] is all about.
1. Needle not seating properly. This needle is usually caged & the slightest contaminant, especially thread tape & the like, can cause not seating properly.
2. Float level too high.
3. Perforated or leaking float filling with fuel.
4. Overpressured & possible because apparently many current kits [meant to fit multiple vehicles] do not come with the right spring for the WW2 Jeep engine. Use your old spring.

I have tried to eliminate (by testing and not guessing) why the carb is flooding. Part of this was by fitting a new carb kit. Yesterday I removed the carb, striped it down as far as possible and cleaned it with carb cleaner and compressed air. I also striped the cold starter (choke) assembly, the mating surface of the disc wasn’t badly scored but I lightly polished the face with some fine metal polish anyway.
I then reassembled the carb, this time using the original jets (but new fibber seals) and compared the old jets with the new ones as I installed them. I couldn’t see anything of any difference between the old and new jets. I also used the old float and retainer arm (When I fitted the new carb kit, I tested the old float to make sure it was sinking, the old float was fine).
So I now have a carb striped and cleaned for the second time, fitted with all the original jets and float. With the top section of the carb removed, I tested the float jet by blowing into the fuel inlet, even without the float fitted the jet would shut off the air flow when the top section of the carb was inverted.
As previously mentioned, to try and eliminate if the flooding is down to the newly rebuilt fuel pump, this was taken out of the circuit and the aux tank connected directly to the carb inlet. With this set up, the only pressure acting on the carb is from the head of pressure in the tank, this was varied by me raising/lowering the height of the tank in relation to the carb.
When I look down the throat of the carb, I noticed that the butterfly valve is fully closed. I’m used to working on old motorbikes, and some require a small gap between the body of the throttle body and the valve. Just wondering if there should be a gap for these Solex carbs?
With the carb back on I tried starting again but, just had the same issues. Took the carb off and the inlet manifold was full of fuel again.
By the way, I have also tried fully open the throttle in previous tests, but it made no difference to the outcome.
I have already had the valve cover off in the past when I first attempted to check the valve clearance, and couldn’t see any valves stuck open, this is why I feel a second pressure test will not show up anything. However, with that said, I think my next move will be to go back to the basics and start again. First by checking the static timing for the ignition, then check the valve timing (even though none of these have been changed since the jeep was running 3 years ago). Once these have been checked and the same issue happens when cranking, then I can only think that the issue is down to the carb/fuel/air ratio?
However, if anyone has any other ideas I could try, then feel free to let me know.

Many thanks

[moonus]

Hello all. I finally got the jeep started.
In the end I fitted a new Solex carb, as the original one just kept flooding and no matter what I did with it, it wasn’t going to work.
After fitting the new carb, I went for the first start, and although the engine wasn’t flooding anymore it still wouldn’t start. So I went back to the basics, and used my newly purchased TDC whistle. Once I had found TDC for piston 1 using the whistle, I took the distributer cover of only to find the rotor arm pointing at positon where number 3 HT lead should be. So after changing the HT leads around in order to suit the firing order, I went for another start and it started first time. I’ve only had it running in the garage as it’s still not ready to go back on the road. The engine is popping a couple of time at tick over, so I’ve had the plugs out and they are all a bit black, but this could be down to a faulty ignition or the carb needs setting up a bit more, so I’ll do a bit more testing once I get the jeep back on the road. At least the jeep is running.
Thanks all
Roy

[Joe Gopan]

Do not be discouraged, there are some issues with carburetors that only a trained technician can remedy.

[majmacs]

Do not be discouraged, there are some issues with carburetors that only a trained technician can remedy.

Ironically, that is some very discouraging advice..........

[Joe Gopan]

The truth is blunt at times, face it, not everyone who owns a Jeep is a mechanic. Why do you think the Army has so many occupational fields and performs aptitude tests on it's recruits?