Oil Cooler Lines

[74Argosy24MH]

Single flare you will see the edge of the tube on the outside of the flare. Double flare folds it back inside (the largest part of the flare will be a fold in the metal). These are used for the compression and sealing of the two layers (higher pressures like brakes). If you have an o ring it is entirely different. Take the fitting to where you have the lines made, they will be able to match.

John

[59toaster]

Ok skip the double flare. That's a different flare alltogether. Not sure what they call that one. Hit Sears and find somebody in the tool department that has a clue and show them that flare. They should have to tool to do it. May just be an nipple adaptor for a standard flaring tool.

Alternative #2 if you can't find the right flare tool is find a brass adaptor that will go from that style fitting to a double flare.

[74Argosy24MH]

For your future reference if you do want to move the coolers (I really don't like stacked coolers). I moved my trans and oil coolers behind the rh headlight with ducts and fans like Brett mentioned. I changed from 2 round to 4 rectangular headlights, sealed around the ducts so all air had to go through the ducts. Your grille is wider than mine so airflow will be easier to get.

John

[zduke4x]

While you have things apart...I would recommend checking the condition of your fan clutch....I replaced mine and here in Florida it sure made a difference in reducing temps especially at slower speeds....lol...jem

[swebster]

John, very nice! I hope my fabrication skills match yours someday. I can see me doing something like what you've done in the near future.

I've checked the fan clutch as recommended and it seems to be in working order. My issue has not been cooling at low speed/idle cooling (runs 180 - 190 when below 30 mph OSAT 80 degrees) it's when I'm at speed (210 - 220 level) and climbing (225 +). I'd like to see her below 200 if possible at cruise leaving me room for the climbs.

Also, I looked closer at that fitting and it does appear to be a "flaired" flange, almost like it was crushed into a flange about a half an inch from the end. Heading to Tractor Supply at lunch and have a call into my buddy at the heavy equipment place.

BTW - Thanks a ton for all of this advice. I really don't know how people did this before this forum!

[59toaster]

Originally posted by swebster@myrvadvanta
John, very nice! I hope my fabrication skills match yours someday. I can see me doing something like what you've done in the near future.

I've checked the fan clutch as recommended and it seems to be in working order. My issue has not been cooling at low speed/idle cooling (runs 180 - 190 when below 30 mph OSAT 80 degrees) it's when I'm at speed (210 - 220 level) and climbing (225 +). I'd like to see her below 200 if possible at cruise leaving me room for the climbs.

Also, I looked closer at that fitting and it does appear to be a "flaired" flange, almost like it was crushed into a flange about a half an inch from the end. Heading to Tractor Supply at lunch and have a call into my buddy at the heavy equipment place.

BTW - Thanks a ton for all of this advice. I really don't know how people did this before this forum!

Thats the problem I just got done fixing on my 88 Burb. Sounds like a plugged up radiator to me.
Going down the hwy with the A/C on I would creep up to around 215-220. It held it but as soon as I got off the hwy I was introuble. THrow it in neutral and turn off the A/C. If I didn't run the A/C I did ok. Now I did have an issue with the replacement fan clutch I put on was as bad as the one I replaced. Thanks for selling quaility parts Auto Zone!

New fan clutch and new radiator and now it's fine. Getting off the hwy and idling in gear I may get to 215 but once the Aux fan kicks in (it's active at about 215) it holds it. I'm looking for a thermo switch that comes on around 200. On the hwy it runs 200-205, might tickle 210 on a long hill. That's what GM says it should run. My truck has Fuel injection and runs a 195 degree thermostat. running too low of stat would cause the Air pump to become active and possibly go into open loop. Both would cause run problems on my truck.

With your not having Fuel injection I would go with a 180 thermostat. You really want to runn around 180-200 range. That actually helps keep the oil clean by getting any moisture in the oil to vaporize and get sucked out by the PCV.

[swebster]

OK...been to three places and no one can (or is willing to) make new lines up for me. I did however find out what the part numbers are...so if anyone else needs to replace these here it is:

Upper Oil Cooler Line: GM 14051374
Lower Oil Cooler Line: GM 14054377 (discontinued but may be available from Workhorse...I'm checking)

[59toaster]

Originally posted by swebster@myrvadvanta
OK...been to three places and no one can (or is willing to) make new lines up for me. I did however find out what the part numbers are...so if anyone else needs to replace these here it is:

Upper Oil Cooler Line: GM 14051374
Lower Oil Cooler Line: GM 14054377 (discontinued but may be available from Workhorse...I'm checking)

http://www.gmpartsdirect.com

Hmm checked and not available there either. Had good luck with them in the past.

[swebster]

Uppers are available but lower is no longer made (which really doesn't make sense if you think about it!). I guess I could get two uppers and reshape one to fit the contours under the frame support but he timing to order these parts would put the completion of these repairs well into next week.

I'm kind of getting into the aux oil cooler idea at this point.

[87MH]

FWIW (for what it's worth)

I have been involved in industrial engine cooling design in the past, and don't know how much would carry over from permanently mounted engines to the 454, but.....

the air/liquid heat exchanger is usually designed for a 70/30 or 60/40 split of the water/oil cooling loads. In other words, the oil cooled 30 to 40% of the engine heat load, and water cooled the remaining 60 to 70%. This is a fairly significant number, indicating that the oil cooler should definitely not be underdesigned.

I found another website while researching filters that reported that the oilpump of a 454 puts out about 6 GPM @ 3000 rpm (that will empty a 6 qt sump in 15 seconds!). I don't know how the flow is split engine/cooler/filter. Bottom line is that it appears risky to me to bypass the radiator/oil heat exchanger.

As far as the tranny, mine comes out of lock at 2500 rpm, and I keep a close eye on the rpm/speed difference, and manually drop to a lower gear when I confirm that the torque converter is slippng.

Any motor heads out there that may have numbers specific to the 454/TH400?

[IPM]

of around $4/ft. Expensive but will hold up to anthing your MH can through at tit. Trim your original hose fittings to accept new hose (slide on) or buy new fittings. Use hose clamps to attach hose to fittings. Go to a friendly pick and pull junk yard and get an oil cooler from a turbo volvo car. they are nice units. Got mine for $10. Plumb two of them together in series for extra cooling capacity. Aftermarket coolers of similar quality are very $$$. I moved my coolers to the side away from the radiator and added an electic fan just for those coolers.

[59toaster]

Originally posted by 87airstream345
FWIW (for what it's worth)

I have been involved in industrial engine cooling design in the past, and don't know how much would carry over from permanently mounted engines to the 454, but.....

the air/liquid heat exchanger is usually designed for a 70/30 or 60/40 split of the water/oil cooling loads. In other words, the oil cooled 30 to 40% of the engine heat load, and water cooled the remaining 60 to 70%. This is a fairly significant number, indicating that the oil cooler should definitely not be underdesigned.

I found another website while researching filters that reported that the oilpump of a 454 puts out about 6 GPM @ 3000 rpm (that will empty a 6 qt sump in 15 seconds!). I don't know how the flow is split engine/cooler/filter. Bottom line is that it appears risky to me to bypass the radiator/oil heat exchanger.

As far as the tranny, mine comes out of lock at 2500 rpm, and I keep a close eye on the rpm/speed difference, and manually drop to a lower gear when I confirm that the torque converter is slippng.

Any motor heads out there that may have numbers specific to the 454/TH400?

Uhhhhh your TH400 has lock up? I was under the impression they didn't have lock up. They have no brains (electronics) and other then the kick down solonoid they have no electrical connections. They have a modulator but that's it.

I'll have to pay attention to my tach better. I know it stays rock steady at 2800 at 70mph. To tell you the truth that makes sense because even when I hit a hill it doesn't seem to change enough to sugest slippage.
Ok let me get out the shop manual and see what it says. When I got this truck I though the converter was not staying locked. I was getting a weird serge on the hwy. Somebody on a Truck forum said it didn't lock up. I ended up tracing the serge I was getting back to a bad EGR.

[swebster]

BTW - I found a radiator shop that is making up new lines for me. It took quite a bit to find someone who knew what these were. I have the entire ordeal on another thread if you are interested

http://www.airforums.com/forum...9902#post49902

Its about my 345, but some other members have chimed in with similar stories about their tow vehicles

[87MH]

Eric:

I have never rebuilt a TH400, and maybe I should have used the term "stall" instead of "out of lock".

In third gear, there is a linear relation between the tach and speedo down to 2500 rpm (when going up a grade ((slowdown)) situation), thereafter, the transmission appears to keep the engine at 2500 rpm, pretty well independent of the speed, until the engine is able to produce enough power to get the beast to speeds in excess of the magic 2500 rpm. This 2500 rpm "unlock" or "stall" is happening about 40 to 42 mph, just about where I like to run max engine speed (3200 rpm) in second gear. I have let the unit stay in third down to about 30mph in third, and it does not appear to want to downshift on its own.

I have learned to live with the situation, and use my own judgement as to whether or not drop it manually down to second.

One of the reasons I am so paranoid about the "stall" point is, given the weight of the bus, the torque the 454 puts out, and the relatively small reservoir of transmission fluid, I suspect that heat in the tranny builds in a hurry in any "out of lock" situation. I therefore try to avoid any tranmission slippage at all.

The next big project on the motor home is the installation of an all new instrument panel. First, I have a hard time reading the present guages, (always seems to be an excessive amount of glare), and second, in my opinion, the amount of information displayed is woefully inadequate.

I'd appreciate criticism on my thoughts, and also what others in the forum would include if they had carte blanche in designing an instrument panel.

It is, after all, my toy, and have often explained to the AB that it is WAY better than a live mistress -- she ALWAYS knows where to find me!

Thanks,

[59toaster]

Dennis:
Ok that makes sense. I thought I got gyped and didn't get lock up.

Mine has FI and the computer controls the kickdown instead of having the full throttle/passing gear switch like yours has. It seems to automaticlly down shift. It comes out of thrid around 30mph on its own and then out of second around 10-15. Booger is the FI wants to idle at 800 RPM in gear. At that speed it's still pushing. It is set that way factory. I am trying to figure out if I can back it off to around 600 to get the tranny unloaded. It will idle 1k out of gear. Sounds high but that's the factory set. I think it has to do with the MAP sensor. I think the signal may become weak at lower RPMS and possibly give a bog at take off. Still researching.

88 was only the second year they used FI on the trucks so it's still a bit behind current set ups. Heck it's down right archaic compaired to systems that are on Toyota's at the time. The FI in my 73VW was a better design except it did not use a O2 sensor. If they used a MAF sensor or a Speed density they could have dropped the RPMS.

[swebster]

Finally got both oil cooler lines made up for $50 at a great radiator shop. Then made up the nipples, replaced the fittings and cut to length for me. Ended up a few bucks cheaper than the GM replacements

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