Freshening Up for a 300K Motor...

[TBigLug]

Some of you who peruse over to the 6.9 side of the site have probably already seen it but since this is strictly a 5.9 related question I delegated it to it's own thread.

Gonna swap my 5.9 and tranny into my '86 F-250 next spring. The motor has 300K on it and no idea if anything's ever been done to it. Once I get the motor out of the truck I'm gonna have the tranny rebuilt while it's out.

My question resides around the motor. What can I do to freshen it up without doing a complete rebuild? I don't know what it's gonna cost but I'd like to keep the machining to a minimum. Should I do just rings and bearings along with a gasket set or just do new gaskets and call it good or whatcha got in mind...

This is my first 6BT but I'm definitely stoked!

 

[argve]

if it were me I would toss it in there and enjoy it - it's probably running fine currently correct? I live by the rule "if it's not broken then don't fix it until it is".

 

[superduty12v]

id do the gaskets and if your gonna freshen it up do a head gasket and studs in there. just got mine with 234k and it runs great. every I-6 ive seen gas or diesel outlasts every engine ive ever looked at

 

[crashnzuk]

If it's a good runner, I'd just do gaskets and call it good.
Travis..

 

[82F100SWB]

Yup, re-seal it and put it in, unless there's something not right with it currently.

 

[TBigLug]

Gotcha, it does run great right now. No excessive blowby or strange noises. I do like the idea of head studs while I've got the heads off doing gaskets anyway. Thanks.

 

[crashnzuk]

Studs are probably a waste of money unless you are gonna put a ton of boost to it.
Travis..

 

[superduty12v]

just insurance with the new gasket.just outa curiosity i got a crack in my exhaust manifold on a 24v i heard that it could warp the head and blow the gasket but that seems a bit extreme. im missing a mounting bolt too so i figured id just grab the BD 3 piece manifold. any other issues i could have with that?

 

[Exekiel69]

If it runs well You just want to do all seals but there isn't need to get in the motor as long as it runs well. You want to make sure the IP isn't leaking since it is much easier to do this with the engine out yet not terribly hard with the engine already on the truck. Order the seals from cummins, with engine serial # on hand and ask for seal WITH the wear sleeve.

The guys running with studs are pushing above 40psi, I usually keep it around 20psi with some bursts up to 30psi but don't need it higher to pull equipment, etc. Might want to check well what HG You should get since there are several good options, the .20 thicker HG (sp?), the marine and O ringed HG.

 

[TBigLug]

I looked into the head stud kit. At $400 ish I think those might wait until I need them. Looks like a gasket kit and away I go.

Where would the IP be leaking from? Mine already leaks from a weep hole at the back of the pump but only after the PO worked on turning it up.

 

[MMeier]

Kill the dowel pin if it hasn't been done yet .

 

[TBigLug]

Dowel's been killed. What about valve springs or valves? Anything need to be done there you think? Do the springs wear out in these engines very often?

 

[argve]

I have not heard of them wearing out but I changed mine to the higher pressure springs because I wanted two things. One being I ran an exhaust brake and wanted max back pressure out it and two was I wanted to turn higher rpms past the stock gov. so I wanted to make sure they got closed at above the 3k mark. They weren't all that expensive so if you are looking to do either one of those in the future now I guess would be the time.