CUCV starting problems

[2deuce]

I bought the M1009 as a parts vehicle as it was supposed to have a bad engine & trans. I put in a new starter and glow plugs and batterys and it started up nicely. The next time it acted like the glow plugs weren't working, it would't start. Tried it this morning and it started as soon as the wait light went out. Now this afternoon it won't start again. Do these symptoms point to the controller? Anybody been here before? and found the solution? Thanks, Greg

 

[acetomatoco]

What is your voltmeter doing... you should see the glowplugs cycle there... Sometimes a restart on a warm engine after a couple of hours with no glowplugs because of residual heat takes quite a bit of cranking...two new batteries will take it...hopefully you put in the 6TNs or 31Ps....and gave them a good charge...

 

[CCATLETT1984]

first, do you hear a click when you turn the ignition on, if you dont, the glow plug relay on the firewall is acting up.
if you hear the relay when you start it cold, but not after its been running, the there is a temp switch that has gone bad.

 

[2deuce]

My hearing isn't so good anymore maybe I'll replace the relay and hope thats it. It wasn't started for 2 weeks and wouldn't start. Let it sit a few days fully expecting it not to start this morning but it fired on the first revolution. 5 hours later, won't start. I did put in group 31 batterys. they spin it very fast. Thanks, Greg

 

[CCATLETT1984]

if that relay works, you will hear the click from inside the truck, its very pronounced.

you can also try bypassing the temp sender that might be the issue. next time the truck doesnt want to start, take a short jumper wire and jump the two wires that attach to the screw-in plug near the front of the drivers' side head.

 

[mangus580]

First I would determine for sure if the glow plugs are cycling at the time it wont start. If they arent, the Temp switch is a good place to start. The relay could also be malfunctioning, or possibly (maybe even more likely) the controller card is failing. If the glow plugs are working, you have a fuel related issue. Try to determine if when the problem occurs, if its parked nose uphill or not. Some truck develop air leaks in their fuel lines, that only cause an issue when parked nose up. I know mine does this, if the fuel tank is low enough. Very strange, i know.... but its true.

 

[CCATLETT1984]

mike, one of these days, we need to write up a checklist for these issues, including pics of the areas in question and post it on the site. I'll be happy to do it, but we will need pics of unmolested trucks since i just us a manual switch and the changes under my hood would throw some people off.

 

[2deuce]

I wondered if it could be a fuel problem so before I tried to start it this morning I opened the air bleedoff on top of the fuel filter. I thought I'd just bump the starter to see if there was any air in there and then check if it got wet with fuel. Wouldn't you know it, it started on the first revolution the first time. Squirting a good stream all over. I'm going to try it again in the morning while its cold and see if the temp sensor is malfunctioning. I'll listen best I can for the relay too. Thanks, Greg

 

[2deuce]

After sitting all night it started right up. The part I don't like is it starts like I have it floor boarded then settles down to a fast idle. I don't touck the throttle. So do you think that points to a temp sensor? At least for the not starting issue? Thanks,Greg

 

[2deuce]

I forgot to add I couldn't hear a click from the relay but that might be just me.

 

[mangus580]

You have an air leak in your fuel system. High revving, and starting trouble are major indicators.

BTW, watch your volt meter.... you shoudl be able to see the relay cycle the glow plugs there.

 

[2deuce]

I can't find a fuel leak when its running. It all appears dry. I did change the fuel filter before I started it the first time. Maybe there is some air in it left from that and I'll try parking it nosing downhill next time it starts. It won't start again now. I thought I'd change the temp sensor in the mean time. There are 2 sensors in the water jacket one in front near the glow plug, it has 1 wire to it and one in back on top behind the air cleaner it has 2 wires to it. Both are on the drivers side. CCatlett said it was in front with 2 wires. Can't find that. Thanks, Greg

 

[mangus580]

You wont see fuel leaking generally. The fuel line from the tank all the way to the fuel pump is a suction line. Its very easy for it to suck a little are, and cause you all sorts of grief. The temp sensor is in the back on the drivers side head. Has 2 wires on it.

 

[2deuce]

Thanks Mike, I found what I thought the sensor might be and took it to napa. They said they would get me one tomorrow. As far as the air leak, that will be a pain. After the engine is warmed up it doesn't run steady like it should it doesn't change speed hardly at all but a very subtle changes in pitch. I was hoping that would clean itself out with a good run on the freeway but I noticed in some documents in the glove box that when it was excessed to the USDA it was noted among some other things that it had a high rpm miss. It doesn't say it was corrected. Sounds like a air leak has been there for some time. This truck had been sitting at the Oregon State University dairy parked for 4 years I was told. I swear it had to hold the record for mouse and wasp nests. The starter was pulled out of it and 2 cans of starting fluid under the seat tells me its been hard to start for awhile too. Thanks for your help. Greg

 

[Michael]

Do not use starting fluid if there is any chance your glow plugs are working.

It sounds to me like you have the famous pressure switch air leak. Search the CUCV part of the site for pressure switch.

 

[2deuce]

I think I know where it is, but how does it come out?

 

[Michael]

http://www.steelsoldiers.com/index....ays=0&postorder=asc&highlight=pressure+switch

http://www.steelsoldiers.com/index.php?name=PNphpBB2&file=viewtopic&t=8835&highlight=pressure+switch

http://1plant4u.smugmug.com/gallery/2307658#120625686

I cleaned up the pdf mentioned in the second link and sent it to the person who posted it. I can email it to you if you need it.

 

[Michael]

I just uploaded scans of the instructions for vacuum switch replacement to my smupmug account. They are much better than the pdf mentioned above.

http://1plant4u.smugmug.com/gallery/3467291#194953668-O-LB

 

[2deuce]

Ok, I'm even more confused now. I ordered the pressure switch from Owens and got it today. Pulled off the fuel filter which had no fuel in it to speak of and discovered the pressure switch is MIA. Just dust and cob webs where it should be. Wouldn't it leak out the hole with the engine running? I see no leaking whatsoever! I don't know what to think now except that fuel appears to run back to the tank when the engine is shut off because the fuel filter only has a little in the bottom when I took it off.
Thanks,
Greg

 

[2deuce]

I took off the base and the pressure switch hole never was open. This base never had a pressure switch. I've got to look for a leak elsewhere.
Greg