I am new to forum,but I have seen the knowledge of the members and hope you all can help. My buddy has a 96 dodge cummins that had the head redone about 6 months ago. Today he found an oily film in his radiator.My question is did his head gasket go or could he possibly have another problem.

 

About the only other likely problem could be a blown oil cooler.

 

would this make the oil guage jump around?

 

Do you know if the head bolts have been re-torqued since gasket was changed? How much oil was in overflow bottle? If head HAS NOT been retorqued, do it, and drain and clean overflow bottle(not rad yet), and soak up oil on top of rad(if any). Check for air bubbles in coolant.


Keep an eye on coolant for a while before doing anything else, to verify problem is fixed. You will know if lots of bolts were loose, that you've found the problem. It's touch and go if head gasket will reseal(depends how distorted it got and how loose bolts were), and may have to be changed again.


If head bolts are all tight, and oil just started to show up, it still could be from gasket, or oil cooler as Infidel stated, at which point you'll have to do more testing to determine which one it is. Keep us informed as to what you've found.

 

No the head bolts haave not been retorqued, but they soon will be. As for the overflow, enough so you could wipe the oil out with your finger. When I first posted I did not know but there ARE bubbles in the coolant. Haven't had the chance to work on it yet because of work. We plan to start in the morning and will let you know the results. Thank you Torque for the advice.

 

You might check on the type of gasket, some need a retorq, others can be ruined by it

 

It could either be ok or ruined now, so it won't matter to try retorque and see the outcome(simplest measure to do first). If retorquing seals the head gasket properly again he's good to go, if not it will have to be replaced again as previously stated .

 

After a headgasket replacement an oil sheen is common, and should be easily removed and then will not return. If the oil is thick and creamy, then start thinking about a headgasket seep. If the oil is filmy and the film is growing in thickness, then look to a leak in your oil cooler.

As for retorque on the headbolts, that is the worst advice I ever heard. The OEM headbolts are a torque set and then turn to stretch type. Which means that you set them to an initial torque value, then turn the bolt a specified additional amount, and the bolt shank is stretched to acheive the proper torque value needed for the life of that installation.

Now, if someone is (there is no other word for this) DUMB enough to reuse the OEM headbolts on an OEM gasket, then you are screwed. Once an OEM headbolt is set to the proper stretch it changes the strength and tension properties of the bolt because the steel is now slightly twisted and the forging grain of the steel has been slightly fractured, and a used headbolt will never properly seat an OEM gasket no matter where you set the torque as it is like pulling a rubber band.

If this has happened, you are into a new headgasket and new set of headbolts. Also, be real careful pulling twice used headbolts, they like to snap off just about 16th of an inch above the threads, as the narrower shank is where the twist takes place.

If an aftermarket solid copper headgasket was used, then the old OEM headbolts may be used as long as the headgasket manufacturer's torque specifications were followed. Again, you do not retorque the bolt unless the headgasket manufacturer's instructions call for such action. Although, most copper headgaskets call for studs, and ultimately that is the best all round solution on the little Cummins.

 

that is very true.....and should have used new bolts

 

RCW if you think head bolts have to be chucked every time, you are the one who is DUMB , as they ARE NOT a one time use bolt, NOR do you know what type of gasket he has, it could be retorque type(depends on manufacturer and style). I didn't tell him to remove head and then reinstall with same gasket, merely check for proper torque on the bolts. Could be a stock setup or modded, he hasn't stated yet what he has for setup, why don't you wait until we know what he has found and what mods.

If he is doing this repair he MUST HAVE a service manual of some type, which gives step by step instructions, INCLUDING checking bolt lengths for being stretched, and being deformed/twisted/cracked, and torque specs. As I stated for him to retorque bolts, I never told him to tighten anymore than what they should be(merely if any were loose to tighten down to specs).


Maybe they had forgot to tighten to final torque spec( I believe off hand it is 1/4 turn after 77ft/lbs. with torque wrench(this is a common mistake to miss this last step). Tightening this last step may stop it and seal properly again. He'll let us know when he replies back with what he found.

If you're so quick to jump on someone, maybe you should go to a ford site, you'll fit right in over there.

 

Well, Torque, I had no intention of jumping on someone, but bad advice is just that. By the way I did the metallurgy studies for the steel that is used on those bolts back when this engine series was being developed by Cummins in cooperation with Case for use in their farm equipment. Trust me, they are designed, engineered and the steel is forged for one time use. This is pretty much the case with all engine headbolts since the late 80's. This is a solid engineering solution to avoiding the need to retorque engine headbolts after a break-in period, and solves a long standing problem of owners failing to bring vehicles and equipment back for what used to be the infamous 50 hour check and maintenance, and then wondering why they blew their headgaskets in the first year of operation.

 

Torque, I know RCW from another site and trust me, he most definitely KNOWS what hes talking about. This man has a wealth of CUMMINS knowledge and probably knows more than all of us put together.

 

In case you haven't looked at a calender lately it is now 2005, not the 1980's. Yes that may have been true then but now IT IS NOT. Some people still are stuck in a timewarp with misconceptions of how things were, not how they are today. Metallurgy, materials and practices have changed much since then, including better steel in bolts, and more torque on them to give better clamping force, and better head gasket materials. Why do you think Cummins supplies bolt length tester in stock head gasket kits? It's to check for bolt stretch, not to blindly change them all.

If bolt is not oiled the full length including underside when being torqued, it will be much more prone to be stretched, cracked or distorted more than one that was oiled properly. If you are dealing with hi-power-hi-boost engines, then STOCK bolts and head gasket may not hold extra power beyond their designed safety limit.

As far as giving bad advise, I would say then why don't you back your statement up with REAL PROOF such as a RECENT(2000+) internal Cummins or even Case document stating YOUR facts, I bet we'll never see one. I also know how things work in the real world, and an armchair critic on the internet can fool most people EXCEPT the educated. If you own a shop I see why you tell people this, you gotta pay the bills.

 

Are you actually that ignorant??

You do NOT know this guy and where he has worked and what he has done for the last 25+ years.

 

Nor do you know much about me Dr. Evil, who's the ignorant one with a statement like THAT. Are you an actual certified Mechanic like me or just another obnoxious know it all, because you've had lots of postings, I guess THAT makes YOU an expert on everything(lol). Unless you have something worthwhile to post, don't waste everybodies time.