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Hard starting, Possible failed block heater??

10K views 67 replies 14 participants last post by  articfarmram 
#1 · (Edited)
Hey guys,

My 12-valve has been starting a bit hard lately. In 10-30* weather it takes a few minutes to get her running. It takes about two cycles of the grid heaters and a little throttle application. Thats normal right?? My heads getting spun around now so I need outside input. What I just described is with the truck unplugged.

But when I have it plugged in things get weird. I think my block heater is NOT working. I tested that theory today, by leaving it plugged in for a solid 20 hours and starting her in 30* weather. It took 3 cycles of the grid heaters, a good bit of cranking, and some throttle to get the Cummins running. This same thing has happened before when I plugged the truck in. Weird ehh?? It’s like the block heater being plugged in is making it start worse:shock:. I know this is completely contradictory of the block heaters purpose and function. What do you guys think?? Have you heard anything like this before or am I just insane? I haven’t felt the block after the block heater has been plugged in for a while yet. I might try that and see if it’s warm. Where exactly is the block heater element located on the engine??

The good news, whether or not the truck has been plugged in, after it starts it runs great!! Smooth and with almost no haze while its warming up (just the normal amount for a cold diesel).

So how can I test the block heater besides slapping my hand on the block??

Other things im thinking could be an issue:

Grid heaters? The voltmeter drops when the grids are on and fluctuates normally. I need to figure out how to use the multimeter I have and test them.

Batteries? Could the batteries be not supplying sufficient power? They're the ones the PO put in. I'll check there cold cranking amps.

Starter? The engine seems to be turning over fairly quickly (I know horrible description). I will pay attention to that aspect the next time I start her cold.

Fuel issue? The OFV should be good, it was taken out inspected and cleaned not to long ago. I also use Power Services diesel supplement (white bottle- recommended amount) in each tank. Should I press the lift pump primer button a few times before I try to start her next time to see if it makes a difference??

God winter makes life a pain……

So what do you guys think??

Thanks in advance:thumbsup::thumbsup: Appreciate any help!

-Garrett
 
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#3 ·
sg, if your truck turns over normal especially after cycling the grid heater 2 or 3 times they are probably fine. but you can get them load tested for free at any parts house. anyway they are not your problem. it sounds like your block heater is'nt working. i can't tell how to check it besides touching the block after it's been plugged in for a couple of hours.
 
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#4 ·
so what you decribbed in the first paragraph of your first post is normal. in that low temp with it unplugged it will take 1-2 cycles and a little throttle to start. that part is normal.

the batteries sound fine. but like the previous post stated. get them load tested for sure. anywhere, even walmart will do it for free. if they charge you, to test a battery, go elsewhere.

read this post.
http://www.cumminsforum.com/forum/94-98-powertrain/347536-last-time-i-forget-plug.html
i think its on page 2. it tells you what to look for on your grid heater. also the last post tells you how to do a volt meter test.


here is also another amazing site about grid heaters and the information. this guy took lots of time for this information.

Grid Heaters
 
#5 ·
have you ever pulled your fuel tank and looked at the fuel sender and checked the ends on it? thats where i had a massive leak from. I fixed it for now but ordered a draw straw. now once the weather changes its going in to fix the problem for good.
 
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#7 ·
Nope. You think that could explain the long cranking?? Lack of fuel flow?

Yep, winter makes it a PITA to do any wrenching. The truck doesnt fit in the garage, which isnt heated anyway. Working outside in snow and ice in 15* isnt an option. Ive done it before and im not doing it again:doh:.

 
#6 ·
Thanks for the links guys!! Great stuff:thumbsup:

I will do the hand to block test to determine if the BH is working at all tommorow.

You guys think the starter is still OK @ 150,000 miles?? I dont know if it was ever replaced by the PO. I dont know much about starter life to be honest.

What about the grid heaters? I will work on checking them, but whats their average life?

Thanks guys!!:thumbsup:
 
#8 ·
i would suspect your starter is fine. the usual problem with these starters is that they will click click click when trying to start. this is an easy fix and lots of vendors carry the kit to fix. this i suspect is not your problem.
Block heater: I had this problem to and how i found it was i had an electrical tester that you could hold up to a 110v wire it it would sound an buzzing sound. i tried it and found out my plug was bad so i cut it off and put on a new plug. 176000 miles on mine and still working.
Change your fuel filter: i recommend a WIX. dont cheap out here.
 
#11 · (Edited)
I changed my fuel filter less than 1,000 miles ago, went with WIX:thumbsup:

-----edit----

The plug that you connect to your home power was the problem, correct?? My plug isnt in the best of shape, when I plugged the truck in for the 20hr test I described I found it was frozen. Water got inside the plug cover and I had to use two channel locks to pry it apart. Then I had to get the ice out if it.

Would a pic of the plug help determine its condition to an electrical guru?? My electrical skills and knowledge are super weak...which im not happy about.
 
#13 · (Edited)
Now that I think about it...

I dont drive the Dodge much these days (winter), I drive the Ford next to it (in the pic) mostly, because I dont give a chit if some fool slides/crashes into it:doh: I see it happen regularly around here..:doh: The Dodge Cummins is cherry and my baby :). The roads have been horrible lately here. Pure ice sheets:banghead:.

The Dodge has just been seeing short quick trips, getting wood, messing around in the snow, etc.

Do you think the cold starts with lots of grid heater use coupled with short drives that probably dont recharge the batteries properly are making my starter, batts, and grid heaters hate life?? I sits and idles for a good 10-15 minutes when its started cold to warm-up (kinda), that probably doesnt do much as far as batt recharging does it..:confused013:

What do you guys think I should be focusing on the most right now?? Determining if the block heater is working??

Hey, I just wanted to say I REALLY appreciate your help and input guys!!:thumbsup::thumbsup:
 
#14 ·
I hear it from outside the truck when the engine is off.
I've noticed the whoosh sound of air in the coolant running though the heater core in the cab mostly after it's been plugged in.
This is because the coolant boils right next to the heater element and adds air to the coolant.

I see the spark right at the male AC plug as I plug it into my extension cord.
If the male plug is wet from driving though slush the plug even smokes a bit right when plugging it in.

The element is a little lower and to the rear of the oil filter, only thing with wires going to it in the area but you can probably feel the heat more at the upper radiator hose than at the element.
 
#15 · (Edited)
I hear it from outside the truck when the engine is off.
I will listen closely tommorow for that. How long does it take after you plug in before you can hear the bubbling??

I see the spark right at the male AC plug as I plug it into my extension cord.
If the male plug is wet from driving though slush the plug even smokes a bit right when plugging it in.
Now that you explained that I seem to remeber the same thing when I go to plug in the Ford, if memory serves me.

The Dodges plug has never done that nor has it smoked or steamed when I have plugged it in slightly wet.....could be a bad sign for plug huh.

The element is a little lower and to the rear of the oil filter, only thing with wires going to it in the area but you can probably feel the heat more at the upper radiator hose than at the element.
Thanks man appreciate it!:thumbsup: I'll give her a feel.....hehe..
 
#18 ·
illflem pretty much said it all. i'm not convinced on the upper radiator being warm. if you feel the side of the block youll know if it's working after plugged in for several hrs. i still suspect your plug ( yes the one you plug to your house) is bad. mine looked ok to but was corroded in the rubber. you see it is sucking up all the grim while following people. cut it off and replace it with a nice heavy duty replacment end. very easy to do.
 
#20 ·
Out of curiosity, at what temperature is your block heater supposed to trigger? The ones on my gas vehicles all trigger at 10 degrees F, so even plugged in, as long as the ambient temperature does not hit 10 degrees, the block heater will not trigger on. This could explain why yours is not coming on.

As far as your batteries go, yes cycling your grids and starting but not driving around much can start to run your batteries down. I have to watch that myself now that the cold weather is here, especially since this is not exactly set up for cold weather starts now.
 
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#22 ·
Out of curiosity, at what temperature is your block heater supposed to trigger? The ones on my gas vehicles all trigger at 10 degrees F, so even plugged in, as long as the ambient temperature does not hit 10 degrees, the block heater will not trigger on. This could explain why yours is not coming on.
Trigger?? I dont (didnt) think they have a trigger at all. I think (thought) they just work when plugged in regardless of the ambient temperature. Thats how the Fords BH works. I would think the Dodge would be the same way.

I sure hope they dont have a trigger!! It would suck if you could only use the block heater below a certain temp.
 
#24 ·
wet thud im pretty sure ours just cycle. ive plugged mine in as early as 40 degrees and still had mine heat everything up over night. smoken gun, i still have my doubts your heater is whats causing your hard starts...because mine had the same symptoms as yours. granted its not helping but i dont think its the problem. idk if this is a good experiment or not but its what i use everytime i get get air in the system. crack a high pressure injector line and crank the truck till it fires and then let it die. shut the line back up and then crank again. if the truck fires right up i would take a guess that you are having some kind of air enter the system. if you can pull your tank, the main thing to look for is the metal push fittings on your fuel lines on the sender as well as the metal fuel lines themselves that come out of the sender. the metal lines want to corrode and break down and those push fittings are the biggest joke i have ever seen in a fuel system. plus they make a slight pinch point in the line as well that makes them want to corrode the fuel line right at the sender. just something to look into, because since i got the air out of my lines my truck no matter how cold fires up on the second crank....once i adjusted my idle back to factory specs.
 
#25 ·
No thermostate on them. The block side is a heater element just like a water heater and the cord is just a plug. More than likely the cord went bad as they tend to be the weak link. I replaced my original block heater at 275k miles when I swapped motors and it was still going. Another thing to check is the connection of the power cord to the actual block heater itself. The flimsey boot may need to be reconnected to get a good connection. As said before I can usually hear a small arc or spark as the flug is connected to an extension cord as it is a heating element picking up a load.
 
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#30 ·
Check to see if you have resistance with a multimeter!!!That will tell you if the block heater is intact. Did you also consider a Zerostart?
 
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#31 ·
did you take your intake horn off and see if the grid heaters are working with the key on postition? run the cycles atlleast twice. they should get hot and glow a little. you will be able to tell.

if they are working with the key on. then i bet your plug is bad or the plug has a bad connection inside of it. and the hard start this time could be the batteries getting weak from messsing with it.
 
#33 · (Edited)
Weird things are a foot…or maybe im just extra paranoid now:confused013:

Went to start the truck today and it didn’t go so well… It has sat for a day or two without being run in 20* or less weather. Now, part of the problem was the run down batteries. Though they had to have some juice to pull this start off. It took six or seven (at least) cycles of the grid heaters with 10 seconds (approx.) of cranking in between each grid cycle before it fired up. It only gave a hint of trying to start a few times before it actually started, it doesn’t start and die or do one of those almost start things just to be clear. As always once it is started it runs great, no abnormal knocks, misses, etc.

I then took the truck for a 10-15 mile drive and it did something I have never seen (or just haven’t noticed). As usual it warmed up slowly while driving, but when it got to 190-200ish* the thermostat didn’t open and cool the engine like it usually does. It kept going and got to 220* before it opened and dropped back down to 150*. I have NEVER seen it do this (or I just haven’t paid enough attention), is this normal? Is it the cold air blasting the in engine compartment (no grill cover or cardboard over the grill) throwing something off to the point where the coolant temp. gets to 220*?? I was worried it would get to 230* and in the red zone!!:shock:

Anyway, after it dropped down from 220* back to 150* it kept its rhythm of going to 190ish* and dropping down again. Although it kept getting back to 190-200ish* pretty quick.

Does what I described above sound normal?? Do I just need a slap in the face about thermostats and engine cooling?? If so, slap away!!:thumbsup:

Back to the original problem:

Im starting to think I have a bigger problem than I bargained for guys… im starting to think maybe one of my grid heaters isn’t working (I have heard they can be bears to start without both grids) or I have some kind of air leak and I am getting air into the fuel system some where. Or maybe both!!:banghead:

Im working on getting a new plug on the block heater cord (replacing the whole cord or even the heater itself if neccesary), but this is just a small annoyance at this point. The Cummins should start great without being plugged in temps down to -20* no??

What is the best way to test the grid heater function?? Using a multimeter or pulling off the intake horn and looking/feeling for their heat output (yes, I know not to actually put my hand on the grids:hehe:). I asked for a really nice infrared laser thermometer for Christmas, would love to use it if it would be the best test.

What do you guys think about the air leak possibility?? What are some points on the fuel system to check first??

This situation is really not idea (when are they...). I have no garage to work in or keep the truck in (that it fits in) while down and working outside in 15* (without wind chill) weather on snow and ice is just stupid..

As always any help and input is greatly appreciated guys!!

----Edit----

Also do you guys think I should give the button on the lift pump a bunch of presses the next time I start her to see if it makes a difference??

-BTW sorry for the book I wrote
 
#37 ·
Im working on getting a new plug on the block heater cord (replacing the whole cord or even the heater itself if neccesary), but this is just a small annoyance at this point. The Cummins should start great without being plugged in temps down to -20* no??

NEG20* it will start at neg 20. but will be hard. anyways. if you never replaced the fuel lines you should also do that. they suck in air. so you can no really see the leak or smell it. fuel lines can suck in air and cause hard starting problems as well.

as well as your thremo. you can get a new one installed. mine never got close to the red line. but this probally is not causeing the starting problem.
 
#34 ·
The block heater ONLY heats the block. It doesn't change the ease of starting. That's what the warmer engine does.

If the block heater is not working, the placebo effect is the only thing making it harder to start (compared to not plugging it in and starting it cold).

Around here, the weather has been cold, but not too cold (highs no lower than 50s, lows in the 30s). When I go to start it in the morning, I usually have the block heater on a timer that turns it on at about 4 AM and I start it around 7. The block (before starting) feels obviously warm (60-80+ deg F) ALL over the engine. radiator hose: warm. Intake manifold: warm-ish.

I have been too lazy to replace my bad battery so I have been going on just one for now. It starts up with less than 1/2 seconds of cranking. I don't remember the time I forgot to plug it in being much different. It just idled a little bit rough from being cold.

Yes, you should get your batter(y/ies) tested. Most places that sell batteries can test it for you. Any auto store (o'reillys, autozone, napa) prolly walmart like someone else suggested, maybe even TSC. If they check out fine, but it still cranks slowly, the problem is somewhere between the battery posts and the flywheel :D good luck

If your batteries check out good, I would suspect air leaks. Unfortunately I don't have ANY experience with finding/troubleshooting them, but that's what sounds a little fishy to me. That or the grid heaters
 
#35 · (Edited)
The block heater ONLY heats the block. It doesn't change the ease of starting. That's what the warmer engine does.
Ah yes, the block heater does make it easier to start assuming everything else on the engine is working properly. The block heater warms the engine, oil, coolant, and air inside the engine hence letting the engine start easier (smoother). Versus with cold thick oil, cold coolant chilling the engine (making compression ignition harder), and cold air making for poor combustion.

The block heater is the engine warmer. The grid heaters are the cold start aid. They heat the intake air going into the cylinders. A diesel engine needs the air (once its compressed) in its cylinders to be hot enough to auto ignite its fuel once injected in atomized form. If the air isnt hot enough in the cylinder it results is poor combustion or no comustion at all.

The problem is it should still start great in 20* weather without being plugged in.

Anyway, Thats why I said this
smoken gun said:
Im working on getting a new plug on the block heater cord (replacing the whole cord or even the heater itself if neccesary), but this is just a small annoyance at this point
 
#36 ·
That was typed when I was still half asleep, sorry. I meant more like "it just heats" not "just the block" because it would be kind of hard to heat the block without heating everything else up :)

I also was getting kind of hair-splitty (I'll do that a lot) saying the block heater doesn't make it easier to start. The block heater makes the engine warmer and the warmer engine is easier to start, so yeah, the block heater makes the engine easier to start.

Didn't want to start another pissing contest like in the "slow spooling" thread :buttkick: (or the "air in the fuel" guy from a few pages ago)
 
#41 ·
Im sure this is a stupid question, but how specifically do I pressurize the tank? With a compressor and air gun you mean? Just want to be clear. Please excuse my ignorance.

Will the leak sucking air be very audible?? Where is the most comon place for leaks? Under the hood or in between there and the fuel tank? Or is there no "common" place?

If I wanted to go overkill and just replace all the old fuel lines and what not about how much would that be?? In parts and service if neccesary.

Thanks Bill!!
 
#42 · (Edited)
I have a fuel cap with port on it but it can also be done with an air blow gun wrapped in a rag.
Problem with that method is you need two people, one to pressurize, the other to hunt.
You will probably see fuel dripping from the leak.
Majority of leak spots are in the engine bay but it can suck air anywhere between the engine and tank also.
Take care to find the exact source of the leak, they can drip and fool you.
If you have to replace any of the lines between the tank and engine just abandon the stock system and use hose for the entire run.
 
#43 ·
Thanks for the info Bill!! Really appreciate it man:thumbsup:

Where would I get a fuel cap with a port for testing?? Is the link below what you mean? Or do you have a better one/place to get one? Again, sorry for the ignorance.

Gates 12410 - Fuel Cap/System Tester Adapter | O'Reilly Auto Parts

This is kinda good timing, im about to get a new air compressor and this will be good use of it.

So i'll work on tracking the air leak down and get back to you guys:thumbsup: I will also try starting the truck tommorow without priming to test the theory (if only for poops and giggles).

Thanks guys!!:thumbsup:
 
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