Engine/Transmission (1994 - 1998) Questions on doing some over due maintenance

[CLE-0129]

To start off with I recently picked my 98 3500 4x4 12 valve up in a vehicle trade and have been slowly going over it. Was used as a land scaping truck so it was in need of some repairs. So far I have just done the brakes on it and have been driving it while looking and checking for other things that need fixed. The truck does have 300k miles on it so I know that gaskets and seals are gonna start leaking at some point. Right now I have got an oil leak on it but can't see where exactly its coming from. The front of the motor is pretty coated in oil. Here is what im looking at replacing,

Timing cover gasket.
oil pan gasket,
valve cover gasket, oil filter.
Is there anything else on the front that I should be looking at to see if its leaking from? While im in there im also gonna check out the KDP and make sure its not going anywhere.

One thing I have not found is if I have to remove the radiator and intercooler to do the timing cover. If I can do it with it all connected that way I don't have to open up that system as well would be great.

Im also gonna be doing a new fuel filter and installing a fuel pressure gauge while im in there as well. Was told to also look into checking the valve clearences as well to make sure they are in spec.

If there is anything else that anybody could recommend looking into while im going over the truck please post up. This is my first diesel so just trying to get it back into shape and make sure its gonna last for a while.

 

[MLee]

When I did mine, I removed the fan shroud and the fan. Hardest part was taking the over flow bottles and windshield cleaner bottle off the shroud. left rad, intercooler, ac in place. Do the crank seal and check for a worn grove in the crank shaft. While your at it, do the fuel over flow return valve. If its stock stretch the spring to .05.5" just a s cosh over 1/2" for the proper length, unless you replace it with new. With this kind of mileage every thing is suspect.
Note; Keep the cover bolts as they are removed, cause they are different lengths and it is a hit and miss if you don't. Inside the cover before you button it up, check the tightness of the gear case bolts all 5 of them, one is under the timing gear and you really need a bent wrench to get to it They torque to 18' llbs not to tight but they are thread lock tighted.

 

[CLE-0129]

Glad to hear I can do most of this work with the radiator and stuff still in truck. Sure keeps down on the amount of parts to remove. Would it be better to just replace the over flow return valve rather than trying to stretch it?

Hopefully do some of these things will help with my cold start troubles. Has a hard time starting even after being plugged in. Sometimes it takes giving it a little pedal to get it to start up. Don't know if adding a little fuel to it would help or not.

 

[MLee]

Good your going to get your hands dirty. The over flow valve, if you check the length witll save about 50 clams. Torq tek has one for that price thats adjustable. Check the fuel pressure it should be 20-22 psi at idle and 30 at 2K. Idle should be around 825 rpm auto, in gear, and ac on. sometime you need to just touch the go pedal to start it. Increasing the idle will help also. Increasing the timing helps to, they are usually retarded some, for emissions but they run a little better if they are advanced a bit. Mine was 13.5* and was uped to 15.5* and this was good medium for me. Some do a little more. Cold hard starts could be fuel pressure and maybe a lose of a little prime. The return fuel hose is the culprit in this case, it will not show leakage but air will sift through and the engine does lose its prime. just something else to be mind full of.
The specks I have quoted is for my 95 and there are/maybe better specks for your 98, so get a manual and have agander at it. Geno's is a good source for some of your parts , like the KDP. Good luck on your new adventure.

 

[BigPapa]

Welcome to the 12V world. They're great trucks.

Good advice from MLee.

Personally, I wouldn't mess with the FP gauge unless you just want one. As for the crank seal, I'd get a Cummins 3802820. It comes with a wear sleeve to put on the crankshaft. I just put one on mine but it has 500K on it. Yours may not need it. Make sure the seal and the crank are dry when installing. If you don't want to do the wear sleeve, the seal alone is 3937111. Geno's carries it and the front cover gasket, 3817683. We use Ultra Gray on the front cover at the bus shop, no gasket.
Also, there are six valve cover gaskets, not one. Clean around them good with some brake clean and shop air BEFORE you remove the valve covers. I put just a little weather strip adhesive in the gasket groove to help hold them in place. Make sure everything's good and clean when going back on.

I know you don't want to remove the radiator and CAC but it would make your front cover a lot easier and it would be a great time to change your coolant and clean the outside of the radiator and CAC. They get dirty in the fins and it will help the air flow. If you're going to remove the fan hub from the engine, there is one bolt that is hard to get to. It has a 10mm head. I use a thin box-end ignition wrench.

 

[GAmes]

No one mentioned the fan nut is left hand threads. I hit it quickly on the edge of the nut with an air chisel to break it free. If you don't have an air chisel a long flat blade screwdriver and a bfh will work too. The most used tool in your shop will be a factory service manual. Haynes & Chiltons are good as emergency toilet paper. I prefer the print version.

https://www.genosgarage.com/product/dfsm98-cd/dodgeram-factory-service-manuals

https://www.genosgarage.com/product/dfsm98-print/dodgeram-factory-service-manuals

 

[BigPapa]

Gary, I didn't mention it because I just remove the fan hub from the block, not the fan from the hub.

 

[GAmes]

Having the fan off prevents the hassle of removing the hard to get to bolt and only takes a minute. Just a different way to skin the cat.

 

[BigPapa]

You are correct as usual, sir.

Can't see what the new avatar is. Looks like a thunderbird, maybe?

 

[GAmes]

It's a lousy picture so I need to redo it. Those are U.s. Army Master Aviator wings.

 

[Bob4x4]

Something no one has mentioned there are o-rings on the valve cover bolt,some gasket kits have them included some don't

 

[MLee]

There you go, you have a ton of advise and suggestions to keep you busy for a long time. Have fun!!

 

[Missouri Mule]

I get a fire hose nozzle and spray the engine where it has oil on it and above.*
My engine had oil on it. Took to my mechanic and told him to find it the fix it.( he always tell me diesel engine leak oil. I told him i didn't like feeding my engine oil every time I made produce run. *
An earlier exam they thouht it the oil pan gasket. But after they powered washed it.
The problem was the timing cover gasket (actually sealant and the leak was on one side.). A real gasket solved the problem.
The first leak I had was the vaccum pump seal.

 

[BigPapa]

Forgot to mention, replacing the oil pan gasket is a BIG job. I would make CERTAIN it's leaking before I replaced it. At the least, the engine has to be lifted a lot if not pulled.

 

[CLE-0129]

Thank you all for all of the help and info on what to look for on this truck. Guess i never really thought about power washing the engine to see exactly where the oil is coming from. I know i got a lot around the timing cover so maybe its just blowing over the rest of the bottom of the motor as im driving down the road. Is there any certain areas i should watch out for when washing the front of the motor of that way i don't damage anything?

Also looking at replacing the fuel filter on this truck and have been looking at them from Geno's but can't figure out which one is correct for my 12 valve? Is the Fleetguard FS19598 the one i want to get for it?

 

[BigPapa]

That's the correct filter.

As to washing the engine, just don't hold it directly on any electrical connector or sensor and don't do it while the engine is hot. I would suggest using a good spray-on degreaser.