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Higher engine temp with new thermostats?

Thats great to know!

I dont know what thermostats is in it now - but I suspect they have never been changed.

Seeing that my measurement is at the side of the car right now, it might just be a temp drop down there as well.

I suppose its another one of these "ill never know If it changes anything before I try", so Im thinking Ill order them and give it a go. ;)
 
Chances are good that you are actually getting two temperature readings at the moment:
  • Dash gauge which reads from the head above #1 (the one you can see).
  • ECM (computer) which reads from the crossover housing.

Without a monitor (example: Edge), you will not see what the computer sees. Getting a monitor is helpful as the computer makes a lot of decisions based on the temperature probe at the crossover. When that probe fails, the truck acts very odd.
 
That Edge monitor looked very nifty indeed! :) have you tried it in a gmt400?

For all i know, these obd2 Bluetooth dongles my be able to read interesting data as well?

I have an utcomp 3 pro from reveltronics installed at the moment for all my temp and pressure Gauges for the wvo install. Ive Been thinking about tapping the factory sensors to see what the ecm see, If I Could only figure out the Voltage scale of the factory sensors. That said, I am slowly but surely running out of inputs on the existing computer, so maybe Ill have to invest in a second one day when I become rich. ;)
 
That Edge monitor looked very nifty indeed! :) have you tried it in a gmt400?

I used the Insight (non-programmable) and it worked just fine on the '99 Burb even though Edge's site does not indicate they support the GMT400. Added boost and pyro sensors as the ECM did not get those inputs. Only PID that Edge did not seem to have was for the fuel flow and I had to use AutoEngenuity for that.

A Bluetooth / OBD-II device might work, but the bigger question is whether the receiving software knows the correct PID's.
 
Ill definitely start Looking for used Edge units for sale here in Norway! And who knows, there might be a cheepo Bluetooth thingie available that would work until I manage to save up for one(the list of things to but for the car just keeps getting longer the more money I trow at it, haha).

Ive Been wondering If maybe I Could tap the signals going into the ecm - there is a lot of information the utcomp Could utilize, but for the moment it does its intended Job of showing my new sensors.

If anyone know where to find info about the control signals going into the ecm ID be delighted! :)
 
A lot of hummer guys use the edge ii. It’s small and mounts on the square flat dash nicely. Many will use 2 of them, you can daisy chain them and set them up for various monitors. But iirc running more than 2 creates problems.

Instead of straight wvo, what about cutting it with diesel at home to offset the freeze factor?
 
Cutting it with diesel is definitely under consideration. I do believe that the system will work when I get my lift pumps, and I do believe I will be able to run it with adequate temps even without cutting it with diesel. I am however thinking that I might end up adding 10% diesel or so to the WVO just to be nice to the fragile DS4.

But I am of Course on the hunt for all possible improvements to the system, so I want to go the extra mile here as well. I´ve been reading up quite a lot lately, and it seems like there are mountain of improvements that can be done to ensure a reliable and happy 6.5! ;)
 
If You install a front over the radiator, be sure the opening for adjustments is close to center of the fan, if not, when the blades hits air it causes them to flex and eventually break.
I got a set ot thermostats from oriellys, they were made in Israel and looked to be of top notch quality. So far they have kept the engine temps right at the 195 temp range, even in temps as low as 25 below zero F.
I thought I would need a winter front with this truck but after the new stats the temps came right up to where they should be.
OH yeah, I was happy to purchase stats made in Israel, I believe in supporting that country.
 
Thanks for the tip!
I´ve ordered some thermostats now, so I´m excited to see if it makes any difference, or if I´ve just spent money on extra work! ;)
I think that sometimes, with twin stats, one stat becomes weaker and opens too soon, causing too much coolant to flow, or sometimes one stat will get stuck open. I have had stats get stuck in the closed position, fortunate it was a single stat units and right away could tell something was not right. LOL
When working for the Mt. DOT as a mechanic, they had a lot of trucks with the 8.2 Detroit's that had dual stats, every 20,000 miles the trucks went through a complete PM level 2, the stats were removed, pried slightly open and a string inserted between the disk and the body, they then were placed into a container of water and the stats hung so that they were submerged but not touching the bottom and heat was applied. a thermometer was then used and when the stat or stats fell off the string the temp was recorded, if they were not at 192 degrees the stats were replaced.
 
That´s a cool test procedure - so simple, so effective!
I´m excited to see if the change does anything or not - I suppose I´ll have them by me mid next week or so...the joy of shopping overseas parts! ;)
 
When I first tinkered with EVANS waterless coolant in my 6.5td Burb I installed a restricter into the bypass and used one drilled 195 deg f thermostat and a 180 deg f thermostat then settled on non-drilled 180 & 195 deg f stats with restricter inside bypass.

In all decisions on thermostats in a diesel consider the hotter the more efficient the diesel will operate however; the pre enhanced 6.5's (APR 99 & back) had way too many cooling issues to begin with so that is critical in any decision.
 
Thats Sounds like an advanced setup indeed! 😬

I will watch the temps closely with the new t-stats. As Im not really hauling any trailers, Im not to worried, but I will definitely keep a close eye on the temps as the spring arrives! :)
 
So after I got home from my holidays last week, I had gotten the new walbro frb-5 pumps and parts!

Got to it today, thinking it was gonna be a big step forward in the wvo-world. I was wrong.

The new walbros give me only 4psi at the pump head, sometimes even down 2.8 to just before the fuel filter manager, both on diesel and wvo. It ran for a while on wvo, but died out on me again (as the last time). Driving on diesel felt kind of better compared to the old ep1000 pumps, even though they were able to sustain 5-6psi on normal driving.

I was expecting to see a higher psi output, so I am a bit puzzled about what to do. I am wondering if maybe the hose barb fittings I used for the walbros may be sucking in air, or leaking air, or both? I´ve had some mixed results with these kind of hose barbs earlier in the progress.

This is the fittings I used. I wonder if it would it be any use in double clamping them? :
5616956170

I took a shot of the wvo lift pump after I mounted it. The diesel side lp went below it.
56171

The only filter I haven't checked by now is the screen inside the fuel filter manager. I have done an attempt to remove it, but I just couldn't´t get it out and I´m afraid to remove it. I would have thought that if this screen was clogged, the pressure should rise just before it, but maybe I am wrong?
 
Last Sunday, I finally had the time, weather, and courage to have a go at changing the thermostats. Had to fiddle a bit to open the thermostat housing, but once it was done, it was an easy swap. While I was at it, I changed both the coolant temp sensors. Hard to judge the dash gauge, but the glow time seems to be much longer now, so changing the ECM thermostat was surely worth it!

I do have to say I am a bit concerned with this all - after the swap, the car seems to run even colder than before - it will mostly stay around 75C(167F) when driving on the highway, and if I push it I am almost able to see 80C(176F). I´ve been debating with myself wether this is caused by air in the coolant system, or if the new thermostats are faulty!?

I let the car Idle for 30mins today after I´d driven it warm, with the cap to the coolant reservoar open. When I turned it off, the dash temp gauge was at a bit under 70C(158F), and I measured about 66C(151F) on the side of the car. Excited to see if it will run hotter the next time I take it for a drive!

New and old thermostat side by side:
5625356254

The old ones turned out to be 190F stats - probably acdelco as well? Hope I haven´t screwed myself by swapping them out!
56255
 
Diesel engines don't warm up well in cold weather at idle.

Use clear hose to look for air. Any screens before the lift pumps? You measureing at the water drain or ip inlet?

BTW the walbro pumps have a built in screen in the bottom bowl. You can order a course screen. Do not run without a screen or prefilter of some sort or you will trash the pump with dirt. Been there done that.
 
One thing is the idle temperature, but it doesn't´t seem to warm up very well while driving either, which I´m a bit disappointed about. Going to a friend now to get some ir thermography photos of the engine when hot to see what the actual temps is! :)

I have a 200micron screen filter before the walbro on the veg oil side (but have removed the walbro screen), and a 140micron screen filter + the original 70micron Walbro screen on the diesel side. I measure pressure just after the lift pump AND just before the IP.

I just got a software update for my gauge computer, to average the pressure readings a bit more. Exciting times to see what results I get! :)
 
IIRC, the injection pump was designed to run at 5 psi at the inlet. While there is debate about what pressure it should have, that was the spec I got directly from the manufacturer.

Temperatures with the new thermostats do seem a bit cool presuming the truck is getting enough drive time and load; then again, depending on the air temperature, this might prove normal. First thing I would do here is to put the old thermostats in a pot with water and see whether they are operating normally or not. Within the realm of possibilities is that the truck may have a malfunctioning fan clutch (stuck partially engaged) which will keep the temperatures low and extend the time it takes to get relatively warm.

Even with a properly functioning cooling system, at idle, the truck will take a very long time to reach operating temperatures. As WW mentioned, it needs driving to get warm. If it is not possible to quickly get to a highway where driving is long distances at 50 - 70 kmh, this will take a long time to get the truck warm as well.
 
Got some answers about the reality today! I visited a friend who works with ir thermo photographing, and had him shoot a picture of my engine valley:
56261
I also shot a pic of my temp gauges at the same time as he was doing the photos to compare:
56262

Im afraid all the temps here are in C, but it works for an European like me! ;)
The good thing about this exercise was that I was able to verify that my gauges seems to measure pretty correctly. I have a temp probe at one of the injectors that matched what he could measure at the same point. The coolant probes I have down on the frame where my filters are seems to be in the range of what he measured as well. The bad thing was that as he measured the temps, just after I had arrived after 15mins on the highway including a long incline, the highest temp we could read was 80C.

I got a tip on a Norwegian 6.5 Facebook group that the local us car parts dealer had some special thermostats for 6.5s that wouldn't´t get up to heat properly. It seems to be a common problem here in the cold. I went to the store, and it turned out to be Stant 13359 thermostats. I´m a bit sceptical to them as they are not recommended by anyone else in the world, but I went ahead and bought the pair as they weren't very expensive (just 2 times rock auto... sigh), so I figure it´s worth a try to see if they could make me happier.

As for fuel pressure, the new wonderful software gave me better readings! :D I seem to have between 2,5 and 4 at the IP inlet at the moment, depending on the load. When I really give throttle in inclines, it drops down to 1-1,5, and a couple of times, I´ve seen it down at 0,somethingsmall. I´m thinking I´m gonna try to plump in the acdelcos in series again, and see what the readings will be now that ´ve done the complete FTB mod
 
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