Ongoing Work in 2018

Six Page Updates - Mar 7th '18  -  Mar 13th '18  -  Mar 18th '18  -  Mar 23rd '18  -  Mar 26th '18  -  Mar 29th '18

March 7th - Re-assembly


On March 7th, the fuel tank, driver's seat and steering wheel were re-fitted. The tank was connected up and partially filled to check for leaks from the feed pipe. After that was seen to be ok, further fuel was added and I prepared for the first start. Before trying to start, I turned the engine numerous times on the starting handle to try and move a little oil around the galleries. It was around five and a half months since the engine last ran.

It took quite a lot of priming with the pump and starter to get the fuel along ten feet of fuel line. After a couple of almost starts, I ran some fuel down the carb and shortly after that, the engine burst into life, running nice and smoothly. Jessie and Hope were then swapped side to side in the garage so I could get Jessie out more easily to finish off the odds and ends needed to be ready for the season.

This was the first time out for Jessie in the new RAF markings.

-----

March 13th - Battery Replacement


After getting the Jeep running again a week ago, it still proved difficult to start. A couple of days ago, I couldn't get it to start at all. I suspected the batteries were at fault, not providing enough power to the starter and coil. A check of the voltage while the starter was turning over showed the voltage dropping to about 19 volts. While I had been seeing a spark during tests, I suspected it wasn't powerful enough to get the engine started, especially when cold, with thick oil and harder to turn over.

Over the weekend, I ordered a new set of batteries which arrived today. This new set of batteries is the fourth set fitted to the Jeep in my time owning it. While the Jeep isn't used regularly, and that doesn't help them, I felt that this battery consumption wasn't right, so I decided to check into things a little further. Checking the voltage at the batteries after starting, I was getting 25.6 volts at idle. As the RPM increased, the voltage increased peaking between 30 to 33 volts. This was far too high. The regulator is meant to keep it between 27.5 to 28.5 volts but was exceeding this by up to 5 volts.

The regulator still had the cover retaining bolts wire locked from its time in the French Army. Time to open it up and start adjusting. I could only get the voltage down to 28.7 volts, but this was much closer to the desired range and should prolong the battery life.
 

 -----

March 18th - Starter Motor Overhaul


The new batteries still didn't improve the starting problems, with the starter motor struggling to turn the engine past compression when the engine was cold. There wasn't much else to check other than the starter motor. I was concerned I was going to have to splash out £285.00 for a new starter. Whether the motor was repaired or replaced, it was going to have to come off the Jeep.

Hotchkiss crammed a lot more equipment into the rear corner of the engine bay, over the starter. The coil, voltage regulator, distributor, rear battery and alternator all made access difficult compared to the Ford or a Willys Jeep. After a struggle, I got the Jeep started and warmed through. This would hopefully allow starting via the hand crank to put the Jeep back in the garage, as I didn't know how long I'd be messing around with the starter motor.

The first thing to be removed was the battery leads, followed by the voltage regulator. This was the main obstruction to reaching the starter.

 
With that out of the way, the starter could be seen. The various cables to the starter and solenoid were labelled and then removed. The mounting bolts were next, but still difficult to reach with spanners of sockets.
 

 
Finally the starter was freed and removed from the Jeep, then it was time for lunch. After lunch, I began to strip the starter to look for any obvious signs that there was something wrong. The end cap opened about half an inch and stopped; the brushes wires weren't long enough to allow the end cap to lift pass the studs.
 

 
After unfastening further bits, circlips and pins, I finally got the thing apart. That revealed a very dirty commutator. I suspect the starter hadn't been serviced since the French Army engine rebuild in 1987. The windings appeared to be ok, and there was plenty of life in the brushes, but the commutator really needed attention. 31 years of crud had built up, effectively insulating the contacts. That prevented the power going to the coils, and so the motor wasn't able to turn over the engine.
 

 
After a good clean, it was looking much better. I then started to re-assemble the motor, lubricating the moving parts where necessary. Getting the end cap back on was a nightmare, as it needed to be almost fully on to get the brushes in a position to lift clear of the commutator against their springs. However, with the end cap almost on, it was very difficult to get at the brushes! The other problem was the brushes wires, which once again weren't long enough to get the end cap over the retaining studs.

It was a fight that I eventually won, but I did wonder whether I should have just spent the £285.00 for a hassle free life!! The motor tested on the two old Jeep batteries first, then fitted back onto the Jeep. I then tested it again with jump leads directly onto the Jeep batteries, and it turned the engine over.
 

 
With that test done, I then connected up all the wiring again and refitted the voltage regulator. With everything back together, it was time for a proper starter button motor test.

I set the choke and a little hand throttle, pressed the button, and Brrrrrrrruuummmmm!! The engine burst into life. The starter turned over much faster that it had previously, and had no problems turning the engine over past compression.

It was stopped and restarted a few times and all seemed well. The real test will be tomorrow when I'll try a cold start when the oil is thick. For this test, the engine and oil were probably still a little warm from the morning run.

The video to the right shows a couple of the start up tests from late afternoon.

 -----

March 23rd - Ignition Problems Hopefully Sorted?
 

I think I've finally sorted the starting problems. There have been a number of things along the way that needed attention like the batteries and starter, but there have also been some red herrings. Over the last few days, I've worked on and tested a number of components. I even swapped to points ignition and a 12 volt coil, and points with the 24 volt coil!

Every time I pulled the plugs to check the spark, I was getting a good spark. When I changed the coil and switched to points, it ran, but also ran again back on the electronic ignition. I suspected a possible intermittent fault in the ignition switch or wiring to the coil.

It would seem that it was all down to oxidised spade connectors on the ballast resistor before the coil. They were given a good clean and a light tack solder joint and now hot and cold starts are almost instant on the button.

 
I'll try another cold start tomorrow and hopefully all will be well. The batteries are charging at a nice safe 27.7 volts at cruising RPM and the engine idling smoothly at 1200 rpm.
 
 -----

March 26th - Ignition Problems - Finally A Cause?
 

Over the last few days, I've continued to test start the Jeep. Some days it started first go on the button, other times it turned over but just wouldn't fire.

There was obviously an intermittent fault somewhere in the ignition system, but there weren't many places left to look. I had a gut feeling and checked the ballast resistor with my multi-meter. No problems previously, but this time it varied from resistance to open circuit.

I did a brief test by using a jumper wire to bypass the resistor and the Jeep burst straight into life. Switched straight off, I then unbolted the resistor from the firewall to take a closer look.

It was fractured, and sometimes made contact while other times it didn't. I'm wondering whether the load when working, warmed and expanded the metal, ensuring good contact, but when I switched off and it cooled and contracted, broke the circuit causing the starting problems. Anyway, two replacements have been ordered.

-----

March 29th - Ignition Problems Fixed
 

The ballast resistors arrived in the post about 11:30 today. I was keen to see if that really was the root cause of the starting problems. During my other checks, the plugs were also quite sooty, suggesting the faulty ballast resistor has been limiting the output of the coil and so not burning the fuel mix properly. The Jeep has also felt down on power for some time, which backs this up.

So after I made some spade terminals, it was bolted to the firewall and connected up. The engine was primed, the starter button pressed and in less than a second, the engine fired into life. I stopped it shortly after and performed another two cold starts, both ok.

I then took the Jeep for a drive for a few miles to warm the engine up and when I got back, did a hot start which also worked without problems. The school run followed, again without problems until I came to put the Jeep away. That start was a bit more difficult, but may have just been flooded. It started a minute later.

 
Another job I've been wanting to do for ages is a rain cover for the rear window. I often seem to end up parked with the back of the Jeep facing into wind on days when it then starts raining after I arrive. The sides and doors keep the worst of the weather out, but the back seat often gets wet.

However, this job has been on hold as I lost the canvas I was going to use. That was found in my workshop yesterday while looking for something unrelated. The attachment is very simple. The end of the canvas was wrapped around some 3/8 dowel and was glued and stapled. The canvas was waterproofed with some tent sealer.

The canvas slots down between the Jeep roof canvas and the STOP/GO light box, with the dowel preventing it from falling straight through. The loose end then hangs down over the open rear window. It rolls up and is stored behind the rear seat when not needed.
 

-----

Home