how cold is too cold?

[cosmobius]

I just picked up a m1028 last weekend and it gave me absolutely no trouble for 250 miles but when i tried starting it the following day at about 10 degrees, i had to crank it for about 5 minutes before it hesitantly started. i have had diesels in the past and dont remember having that kind of trouble so my question is: how cold is too cold? Without a block heater, should it start easier than this at 10 degrees? It frequently gets below zero here and i plan on installing a block heater but could i have a GP issue?

 

[4bogginchevys]

I bet if you have more than 2 GP's not working it wont start. Many have said no problems without block heater to -10, but then the oil is so thick it's hard on the motor anyways...coolant heater and a glow plug or 2 and she'll fire right up

 

[cosmobius]

I bet if you have more than 2 GP's not working it wont start. Many have said no problems without block heater to -10, but then the oil is so thick it's hard on the motor anyways...coolant heater and a glow plug or 2 and she'll fire right up

Thanks for your input.

So are you saying that at 10 degrees it shouldn't take 5 minutes of off and on cranking unless there is a problem with the glow plugs or is the fact that it eventually started a clean bill of health?

I should mention that it was about 10 degrees when i tried to start it mid morning but the overnight temps were below zero.

 

[4bogginchevys]

should be fast start, if you do an advanced search of the forum you can find a link to a u-tube video where a truck started in colder temps than you mention, no block heater, just good plugs. there's also many threads about testing plugs, and the TM's. Somewhere i've heard that using a thinner oil in very cold temps is fine, but would do more research before just guessing what weight/temp range. good luck

 

[tshermankb]

plugs may not be the culprit. If your fuel pressure sensor is leaking (extremely common) you could be loosing your prime. Combine that with thicker than optimal fuel and it could easily take 5minutes to crank the lift pump enough to pass the bubble.

 

[Sgt Hulka]

My GUESS is plugs. And it ain't gonna get better till you replace them... Not that the other ideas don't have merit. That's just my guess...

 

[doghead]

Take a hour and do some searching on the cucv forum. Take another hour an download and read all the TMs listed in the cucv wiki. Now you will have a much better understanding of the issues that these trucks have. If your truck is stock, just one bad GP will cause the rest to fail(you will learn this by reading the forums). You need to diagnose the GP system and the fuel system to determine your problem. These trucks will start just fine, 5 seconds of cranking or less, at -40*F(mine does, with no added starting aids).

 

[BKubu]

I have recently started my CUCV down to about 15 degrees and it started up quickly. It ran rough for a few seconds until it started to warm up, but it fired off almost immediately...by immediately, I mean I had to crank for about two seconds. I have never had a CUCV that started this nicely. The previous owner failed to tell me about a few things that I am not happy about, but, overall, the truck runs as well or better than any CUCV I have ever owned.

 

[CASESIOUXCITY]

I forgot to plug mine in last night and it started up this morning with the temp at -5 it took about 30 seconds for it to pop off though . I would also say its the glow plugs

 

[cosmobius]

plugs may not be the culprit. If your fuel pressure sensor is leaking (extremely common) you could be loosing your prime. Combine that with thicker than optimal fuel and it could easily take 5minutes to crank the lift pump enough to pass the bubble.

Hadn't even considered that. Thanks for your input. I am trying to locate and download the repair manual to try to trouble shoot this problem.

This morning it was 12 degrees and she barely wanted to turn over. I didnt spend any time messing with it because i needed to get to work but i will check out the sensor when i get a minute.

 

[gaunt1969]

plugs may not be the culprit. If your fuel pressure sensor is leaking (extremely common) you could be loosing your prime. Combine that with thicker than optimal fuel and it could easily take 5minutes to crank the lift pump enough to pass the bubble.

if its that cold and you can get it to start after a lot of cranking, its most likely you lost prime for one reason or another;
If it was a bad plug and you are still useing a resistor 24 v system they would all blow and it wouldent start at all

 

[cosmobius]

I forgot to plug mine in last night and it started up this morning with the temp at -5 it took about 30 seconds for it to pop off though . I would also say its the glow plugs

That makes me think i definitely have some sort of problem. Should you be able to hear the relay for the GPs? My light comes on for about 10-15 seconds but when it goes off, i don't hear anything click.

 

[gaunt1969]

just wait for it. the gp relay stays on for about another 10 to 20 sec b-4 it goes off; I think the lift pump has a check valve and it it is leaking down and looseing prime it could be your truble

 

[CASESIOUXCITY]

You can hear mine click pretty good and also see the volt meter move a bit since they draw quite a bit of power

 

[Monty]

I've had no problems with mine starting at 10degrees, it'll run rough for a couple of seconds then smooth right out. I run 15w40 Amsoil in mine which is a full synthetic oil. Is the truck spinning over fast enough? Check battery connections and work your way through the GP circuit then onto the fuel system. Once you get everything figured out look into a full synthetic oil, most have a better cold flowing ability then a petrolumn based oil.

Read through the TM's they are a wealth of information, and search through the fourms the information you seek is out there.

Chad

 

[cosmobius]

The cranking was slow this morning so i didn't even bother. i am going to start with the electrical system tonight and move on to fuel and then glow plugs. I finally found and downloaded the TMs so this will be a big help.

 

[cosmobius]

OK. I tested the GP System last night and i have come to the conclusion that the relay and the glow plugs are all shot.

The ohm readings were not correct on the plugs and i was seeing 12 volts at the glow plugs even with key in OFF position. I could not test the switch because the engine was too warm. I could hear the relay click so i am assuming that the module is OK. Is my reasoning correct or am i off my rocker?

I think i also have a battery problem. when i turned the key to RUN position this morning, it was in the yellow. I should be in the green right?

 

[cucvcan]

I would start with your batteries. The cranking should not be slow, it may not want to start or run a little rough but with good batteries it should crank robustly.

 

[four_by_ken]

I agree... shouldnt crank slow. My M1008 is slow turning over and gets a little harder to start when its cold. My M1009 cranks like a bat outta **** and starts fine no matter the temp.

 

[91W350]

My M1008 and M1009 both started right up at 14 below. I was kind of worried as we were 370 miles from home and I did not want two dead horses at my mother in law's.