Diesel Running Temperatures

Joined
Oct 23, 2006
Messages
85
I wanted to get some feedback from Turbo 3b and 13bt owners out there as to what they feel is an acceptable running temperature under heavy load. Please let me know what your EGT's and boost are along with what thermostat you are running and if you are intercooled or not.

I am dealing with an 85 BJ70, 3B w/ Axt 10 psi boost. 182 degree thermostat.
Around town it runs at 160-180 degrees depending on how much stop and go.
Flats on the highway 180 degrees EGT of 800 degrees
Heavy load on the highway, as in a 3 mile long uphill mountain pass at 60 miles an hour, my EGT creeps to 1000-1100 degrees and temp will creep up to 230 max, which is not yet in the red zone on the factory toyota gauge, but very close to getting in the red. As soon as I begin to descend it rapidly starts dropping and will drop back down to 160 degrees and stay there until the next decent size hill.
The cooling system is all brand new, rad, tstat, water pump, fan clutch, hose, block was flushed.
Is this normal, or too hot?
If i pull the pass at 50 mph, the EGT drops 100 degrees and running temp drops 10-15 degrees.

I am getting the intercooler hooked up tommorow and am curious to see what affect this has.
Please give me your feedback as I am a lone 3b owner in the US
Thanks,:cheers:
 
Joined
Aug 7, 2006
Messages
76
Location
Park City, UT
I am seeing 1000 EGT and my temp gauge is a little under halfway mark. This is at 5000 ft. elevation going uphill for @ 3 miles. So it sounds like we ara about the same. Around town my truck runs @ 800 EGT and 1/4 of the way over on the temp gauge. I live in Park City, Utah a high elevation town, so i installed an oil cooled Turbo on mine, which helped quite a bit with the Mt. passes. Anyway I hope this helps.

Cheers
 
Joined
Oct 23, 2006
Messages
85
I am seeing 1000 EGT and my temp gauge is a little under halfway mark. This is at 5000 ft. elevation going uphill for @ 3 miles. So it sounds like we ara about the same. Around town my truck runs @ 800 EGT and 1/4 of the way over on the temp gauge. I live in Park City, Utah a high elevation town, so i installed an oil cooled Turbo on mine, which helped quite a bit with the Mt. passes. Anyway I hope this helps.

Cheers

So you are saying your factory temp gauge does not get close to the red zone on mountain passes?
 

lowenbrau

SILVER Star
Joined
Jan 22, 2003
Messages
3,885
Location
Rockyview County AB
I have similar results. I disconnected the wastegate on my CT26 and my max boost went from 8 PSI to 16 PSI and hills that used to get me to 1300f now just barely go over 1000f
 
Joined
Oct 23, 2006
Messages
85
I understand more air=lower temps. But what is considereded
too hot for coolant temps. I have never considered my EGT's to be a problem. But my 230 degree coolant temp on mountain passes is a concern to me. Would 230 degrees coolant temp be of concern to anyone else?
 

lowenbrau

SILVER Star
Joined
Jan 22, 2003
Messages
3,885
Location
Rockyview County AB
I understand more air=lower temps. But what is considereded
too hot for coolant temps. I have never considered my EGT's to be a problem. But my 230 degree coolant temp on mountain passes is a concern to me. Would 230 degrees coolant temp be of concern to anyone else?

Nope. I figure I'm adding years in purgatory if I let the temp get over 240.
250 really gives me the willies.
At 255 I actually take action.
 
Joined
Apr 28, 2005
Messages
450
Location
Bend, OR
HZ-t60, 9lbs boost and I get hot, too hot for my comfort on mtn passes. Once my EGT's hit 1000-1100f, my coolant temps go up. I'm working with the dummy gauge and it goes right up to the red. A while back I used a laser temp and was getting 240f off the front of the head, just before the coolant hits the radiator.

Things I've done that have helped: Alum Radiator, move winch controller - air flow, add Toyota Red, and finally - slow down.

I have a couple granger valves somewhere, and may want to try those to up my boost and see what happens. Also, adding a real temp guage so I know exactly what's going on may help.

We'll see on the way to Moab, as NV/UT, Hwy 50 has plenty of uphills to work with.

Bob
 
Joined
Oct 23, 2006
Messages
85
So from the consenus I have gotten here, 220-230 degree coolant temp on mountain passes is pretty standard. I have done the aluminum radiator, and every thing possible to the cooling system.
I just hooked up the intercooler yesterday, HUGE difference. I did not have to put my foot in it as much, my EGTS, were down 100-200 degrees, and my running temperature barely hit 220 where it used to hit at least 230 and sometimes 235. It also took longer to get there.
So my thought now is turn up the boost and turn down the fuel a little. I know this sounds weird since the air coming out of the turbo has long to go and an intercooler to flow through but my throttle response is better and my boost is now 11 psi instead of 9-10.
Any thoughts about cranking up the boost and turning down the fuel?

:beer:
 
Joined
Dec 15, 2004
Messages
1,126
Location
El Dorado Hills, CA
SC,

I have the exact same issue and concerns...hearing that others are having similar experiences makes me feel better. My set up as of now is:

3B w/ AXT (no IC)
13lbs boost
A/C retro fitted
35's
4.56's
Oil cooler
solid fan
All new cooling system (Rad, hoses, belts, 82C T-stat etc)
4 core rad

I also have a boost, pyro & temp gauge so I know exactly what's going on. I have dealt w/ this issue for years, ever since I added the AC. To be honest, knowing what I know now, I'd have just left the stock 3 core rad in there...

I never had any water temp issues until the AC went in. For several years I just never drove it during the hot months (I'm in Sacramento = HOT summers). Finally in the spring of 05 I "upgraded" to a 4 core rad from 4-wheel auto. Right away my temp problem was worse. I took my rig to Chad Davis (a local rad guru whose solved many a cooling problem for V8 Cruiser guys). He told me he thought the way the 4-core was built was the reason for the problem. He built me a new rad, I returned the 4wheel auto rad and the truck ran great and I thought the problem was resolved...only problem was that summer it never got that hot (like mid 90'sF). The following summer (2006) the heat returned (100+F) and so did my problem. I've run diagnostics out the ying yang (including a compression test, leak down test, you name it) and dealt with every small issue you can think of including a cracked leaky intake plenum hose that was robbing me of boost.

I've since come to the conclusion that with the 4 core & the AC, my little 3B (even w/ a solid fan), just can't pull enough air through to cool it properly. On a hot day I can take a laser temp reading at the top inlet of say 210F, & the bottom will be 190F. You should get a cooling effect of at least 20% (168F in that case)

SO... I went and bought a 3rd battery, a solar converter to charge it, and a low amp 12v 2500 CFM electric fan to mount right behind the radiator. I don't know if this works yet cause we havent had the heat yet....time will tell but I'm REALLY convinced this time that it'll work.

FYI...any ambiant temps under about 90F and she runs like a champ with EGT's well under 1000 (even uphill) and H20 temps of 165 - 200 depending on the ambiant temp. I'm admittedly a total perfectionist have have been told by countless people (Wayne:) ), that I have no problem, I'm too paranoid and to just shut up and drive. It is sad that my beautiful little 70 has seen less than 10,000 miles in the last 3 yrs:frown:

I'll let you all know how the E-fan works out
 
Joined
Oct 23, 2006
Messages
85
So I see I am not alone, diesel bigot has the same issues.
Though I just hooked up my intercooler yesterday and pulled siskiyou pass in southern oregon, and had to put my foot in it alot less, as a result, my running temperature hit 220 max and my egts post turbo were down 100-200 degrees. I think the next solution is more boost and less fuel. Diesel bigot what do you think?:beer:
 
Joined
Dec 15, 2004
Messages
1,126
Location
El Dorado Hills, CA
So I see I am not alone, diesel bigot has the same issues.
Though I just hooked up my intercooler yesterday and pulled siskiyou pass in southern oregon, and had to put my foot in it alot less, as a result, my running temperature hit 220 max and my egts post turbo were down 100-200 degrees. I think the next solution is more boost and less fuel. Diesel bigot what do you think?:beer:

No harm in trying more boost & fuel...worst case scenario is you have to dial them back a bit...One thing to think of though, more boost & LESS fuel means less power overall....increased boost without additional fuel will lower your EGT's but won't do s*** for your power. I think part of the reason 3B's heat up is they have to work so hard to do what we're asking of them. Think about it...I'm asking a 3.4L, 90 HP motor to push around a heavily laden, 5,500lb truck with 35's and all the aerodynamics of a box of tampons up a mountain pass with the AC on in the dead of a 100 degree + NorCal summer:D :flipoff2: I'm surprised these motors don't just take a crap on us:)

I'm no expert, but I think what you want to do is mess around with the easily adjustable things like boost & fuel till your truck is running well and EGT / H20 temps are within an acceptable range given your most difficult operating conditions (High ambiant temps & big hills). IMO, I wouldn't worry about any EGT's under 1,200 in any conditions...these 3B heads will put up with allot.

I've had very long conversations with Reinhart @ Berrima diesel & Andrew at AXT in Australia and asked them what guys do in the Outback with these motors. The general consensus was that to run 3B's in extreme temps (like 100 -120F), the first thing most guys do is run a 4 to 6 core aluminium rad...then they upgrade to a 5 litre expansion tank. Little things like making sure you have a good shroud seal and adding additional shroud material underneath the truck makes a difference as well.

I'm interested to know....what kind of ambiant temps are talking about here when you give these EGT / H20 readings?
 
Joined
Oct 23, 2006
Messages
85
The overheating situation has occurred in temperatures below freezing and temps up to 100 degrees. As far as I can tell ambient air temperature has little affect on my 3B getting hot. As per a radiator I added a 24"x19" 2 row 1.25" tubes double pass aluminum radiator. Supposedly according to Northern radiator the manufacturer it can cool up to 900 HP muscle cars. I have a 1500 CFM electric fan and am upgrading to a Louvered shroud kit with a 2300 CFM fan from Northern radiator.
As per my fuel and boost adjustment. I am happy with my power right now. It will pull Siskiyou pass in southern oregon at 65-70 miles an hour. So if I pump up my boost and leave my fuel alone, and hopefully lower my EGT's my H20 temp should be cooler. I think their may be a direct relationship between cooler air going into the motor and H20 temps.

I agree that adding a large overflow will help as opposed to the stock one. As per a shroud the new one I am ordering should help. I think it could also be good to reinstall that factory piece of metal thing, maybe a shroud or protective plat which bolts to the bottom of the frame above the tie rods.

I am destined to beat this problem once and for all!
Diesel Bigot please stay in contact regarding this issue.
Thanks:beer:
 
Joined
Jan 20, 2003
Messages
11,194
Location
Wherever the truck stops!!
Website
wirrell.com
I run the standard 4 core Toyota rad and I do have A/C, my pyro is pre-turbo and it will reach 1150-1200 pulling a hill. I have only ever seen it get hot on the coolant gage (factory) pulling hills in Arizona at 115 ambient temperatures loaded and with the A/C on. When that happens I just shut off the A/C and the temps come back down, even when pulling hills!

Do you guys with the over heating issues have a shroud on your fans?

The FJ55 is running a turbo'd 3B and the stock FJ55 rad reconfigured for the 3B water connections and it too is fine according to the stock gage (no A/C hooked up yet).

How do you pull Siskiyou Pass at 65-70mph unless you are empty? The FJ55 pulled it at 55-60 with a load but I had to watch the EGT's as they were getting up there to the 1200 range pre-turbo. The BJ60 which was heavier loaded did not pull it nearly as fast. Part of the equation is that the 3B in the FJ55 is a fresh rebuild. My last time through there was March and it was relatively cool then.
 
Joined
Mar 29, 2005
Messages
30
3B Cooling

My 70 is set up very similiar to Diesel Bigot's........except for no A/C:eek:

I run a HJ60 clutch/fan, 4 core,GOOD shroud (electrics will not cut it alone BTDT)

I have 0 issues if ambiant is not more than 90F.

BEST Thing I ever did , that made the most difference was do a 1" body lift.
Leads to some of the problem being that the air cannot get out of the engine bay as fast as it is going in.

If I run a solid fan I cannot make the engine temp rise above normal even pulling my 18' travel trailer against a strong headwind.
 
Joined
Oct 23, 2006
Messages
85
To answer the question I pull Siskiyou Pass at 70 mph empty in fourth gear with room to go. I am running 3.73 gears with 33" tires.
As per Cruiser guy and lil joes comments, are you running the factory gauge for h20 temp. Because my factory gauge does not go into the red even at 230 degrees.

Cruiser guy-when you say pre trubo egt's, where is you pyro mounted?

As per the comments on a 1" body lift, I find it hard to believe that 1" would make a huge difference. I guess as an alternative you could trim the bottom of the inner fenders.

Also how much boost are you running and where is you fuel at?
 
Joined
Jan 20, 2003
Messages
11,194
Location
Wherever the truck stops!!
Website
wirrell.com
The thermocouple for my pyrometer on both the FJ55 and the BJ60 is tapped into the exhaust manifold and it is sensing the exhaust temperature BEFORE it enters the turbo. I want to ensure I don't have piston meltdown!

I am running the factory coolant temperature gages.

Both the FJ55 and the BJ60 are running 3.7 gearing in the axles and the FJ55 as an H42, the BJ60 has the H55. The FJ55 has stock size tires and the BJ60 has 31's. Boost is about 9-10 on both with no adjustments to the fuel delivery on either truck. The BJ60 injection pump has not been touched since new and the FJ55 was done when the engine was rebuilt. I will be turning the fuel down on the FJ55 since I can get the EGT's too high if I don't watch the gage.

Is your boost sensed at the intercooler intake or discharge, ie: at the turbo or at the intake manifold? Is 70mph up Siskiyou pass intercooled or non-intercooled?
 
Joined
Mar 26, 2007
Messages
338
Location
Texas
hello

My Bj70 is now turbocharged and top mount intercooler,,,after running a front mount intercooler with A/C and testing it for 5000 miles in the Texas heat, the top mount intercooler is a better set up,,,I have egt temperatures of 685 F (post turbo) at 70 mph on flat...long hills 900F. Water temperature 220 max up hill full load(gear,people,etc) ...Remember this is for a Bj70.
 
Joined
Apr 5, 2006
Messages
83
SC-

I was having similar coolant temp issues with my '82 bj42, axt turbo 3b @ 10psi. I obtained a solid fan clutch and the temp gauge (aftermarket) barely budges from 82C

BTW, you are not alone in the US as a bj owner, in fact you are not alone in Jackson County.
 

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