8V92 condition questions

[JohnEd]

I was over at a friends to day and looked at his 8V92 sitting on a stand.  He bought it as a "running" take out.  Whatever that means.  I hope some might be able to keep me inbounds on a coupkle issues.

Can the condition be determined by carefully inspecting each Piston thru the air box?  I have read that the skirts can be badly scored and the ring groves also.  What is "over the hill?

Is it worth doing a compression check?

The turbo has "a lot" of play in the up and down.  LOTS!  The end play is easily detected but not as bad as the lateral.  Is it possible for me to rebuild this?  I have time and access to some machine shop tools.

I can wiggle the valve rockers sideways a good bit.  Seems excessive to me.  I also noted that one of the four rockers I could reach are not all set to the same clearance.  One seems much looser than the other three.  I read recently that the rack should stay set for the life of the engine.  Given, an 8V92 is supposed to "live" 450K miles, what does the rack indicate as far as how many miles might be on the engine?

Jake Brakes.   Its not obvious but I found the front coil connection on the right bank to be holding by only 2 strands.  The wire does not feel like solid copper and my friend said that the electrical leads are special and can't be replaced with common stranded wire.  True?  Can I repair the stake-on connector on the end and reconnect it to the coil?

Thanks,

John

[Jerry32]

You might get more answers on the DD board too. My engine is in fair condition and I just had jakes installed . The mech found three worn rockers and replaced them and told me theyy do wear and have to be replaced ocacionally Jerry

[DaveG]

As far as the Jake wiring goes, heat and oil are probably the reason most wires are not adequate...but there should be no problem in cutting it off and attaching a new end/connector and hooking it back up.

In the business, a running take-out is just that...an engine that was running when take out of whatever it was in. Doesn't mean much, I know. Unless you are in a pinch, it could be better to pay more $$ up front and get something that has some known history, or stuffing that 'running take-out' could become an exercise in R & R'ing an engine.

[luvrbus]

JohnEd,you can check the pistons and 3 of the rings from the air box but you can not check the 2 lower oil ring for breakage.  

The compression check for a 2 stroke is lot of work but worth it,the engine needs to be running at 900 rpm to get an accurate reading pulling one injector at a time and re timing the injector each time one is removed.  

Turbos have play in up and down  take a dial indicator .008 doesn't sound like much but it will surprise you with the movement  if it turns free and you don't see signs of dragging and oil it is probably ok.

You can move the bridges when the valves are closed and you not going to tell  the mileage by the rack  

The Jake Brake harnesses are not that expensive to buy and are stranded wire  

If I was buying the engine I would make him start it up not that big of a deal to start one on a stand just be careful with the throttle don't ask how I know that    

Good luck

[JohnEd]

DaveG,

I think what he really wants to do is SELL the engine.  He has no history and that is a flaw.  He wanted to replace bearings and other things but I councelled him to let the new owner take care of that as he would probably want "proof".

Luvr,

I told him to get it running on his test stand and get it evaluated by a pro.  It looks like I can adj the valves.  The injectors are an unknown till I read Da Book as others that have come before me.  That air box check data is really good.  The wire in the Jake is really springy and is colored like stainless.  I would say those rockers are shot if I found them in a gas rig but what do I know(really!).

I am curious about another thing:  The roots sounds coruse in another bus.  It makes a metalic sound that doesn't sound good.  I compared it to another 871 and that one seemed quiet. Should you hear the roots as a separate noise to the D din?

Thanks Guys.

John

[JohnEd]

OK, I got more info on this puppy.  He took the engine to DD and asked that they determine what it needs.

They charged him $200 and told him that the crank and cam were both in good shape and there was not enuff wear on the cam or crank bearings to warrant replacement.  I don't know what they did but I am told they didn't fault the pistons or anything in the one head where they removed the valve cover. Turbo also passed I guess.

He has a whole pile of air starters and wants to start the engine so I guess we can do a compression check.  I know his objective is to sell this engine when he gets an idea of the "real" condition and figures what to ask for it. If any have interest you might be able to program his eval to areas that you are interested in.   I can involve myself in monitoring the tests and documenting the true results/findings. Any advice in addition to LUVR's  would be appreciated and might contribute to the "well being" of any of our Knuts that might eventually buy the thing.

I am told that that "new" HT 747 D trans will hook up to this 8V92 and handle the torque.  Correct?  Luvr???



Thanks,

John