T245A Valve guides dilemma

[Sebastian]

After almost a year ago a rod bearing said enough and was disintegrated at 55mph. The engine was taken and, as I was afraid, it needed a a complete rebuild.
Months after (and lots of $$) I had all the parts needed 90% NOS, many from the US, I'm in Argentina.
I chose a decent shop to do the work, they tell me they knew these engines as were contracted by the Army back in the 80's, when these trucks were in service here.
Got the engine back, as used here, with the machining work, pistons, crankcase, valves and cam installed, I have to install oil pan, oil & water pump etc. AFTER tighten the head I noticed all valve guides were installed downwards I mean with the cone end facing down.
Now i have another 2 engine cores with valve guides yet installed, intake guides are upwards, exhaust are down. Why is this done? should I pick my Glock and go for a friendly talk with the man who do this? Should I use them as they are? what could happen?
These are Clevite guides #3338 and #3337 I had to wait a lot for them as they are unavailable in Argentina.

[MSeriesRebuild]

The counterbored end should be up on the exhaust guides, this provides the necessary relief to keep the valves from seizing in the guides during times when high heat is present. The intake guides should have the cone end up, this minimizes oil being drawn up through the guides into the combustion chambers. So yes there is a reason for them being installed correctly. I would insist they be re-done in a newly rebuilt engine if I were you. You don't want to leave the door open for problems to occur.

[Juan]

Sebastián, volviste de España?
Cambiaste de usuario. Espero que te haya ido bien.
Excelente explicación la de Charles .
A que rectificadora lo llevaste

Now in English

Sebastian, are you back from Spain?
you've changed your nickname, Hope you did well.
Excelent explanation from Charles
where did you take your engine to have it rebuilt?

Hope I see you now if you are living again in Buenos Aires.

[Sebastian]

Thanks Charles!
As Juan said, excellent explanation. That's exactly what I need to know before ask for this job be redone.
Now just one more question. What if intake guides (the wrong ones) are taken very carefully upwards with the right tool and installed again in the correct position. Did the guide will suffer any distortion? these guides came in the final bore. I mean they didn't were reamed.
I know maybe valve seats should be regrind but at least I don't have to order and wait for new guides.
I know all this is the shop's fault but I have to be realistic. They surely say there will be no problem as they are, so I have to find the better option to get this job done.

And, yes Juan I'm back in Buenos Aires since Jan 2007.
I sent this engine to Rectificadora Torino in Avellaneda.
En cuanto lo tenga andando me gustaria acercarme por donde estes.
Tengo alguna preguntas que hacerte acerca de estos camiones.
Seguis teniendo la M43?

I'll post the follow up of this story.

[MSeriesRebuild]

If you can figure a way to pull them out carefully, you might can reuse them, however I would certainly run a correct size reamer through them before installing the valves. We have used "bored to size guides" for years, but never trust that, always run the correct reamer through them to be certain, you would be surprised how many we find that are too tight without it. I can give you correct reamer specs if you need them.

[WCarlsrud]

Charles,

I'd love to get the correct specs for the reamers. I'm in the process of putting in new guides. The exhaust guides are sized correct but the intake guides appear to be sized a few thousandths smaller than the .342 minimum.

Thanks,
Warren

[DAP]

Hey WC how you doin, you still in Hotlanta? Did you ever redo the puke yellow ambulance you bought from me. I am working on a MArine coprs mid 50s green M37 now. It is my 20 year project LOL

[MSeriesRebuild]

Charles,

I'd love to get the correct specs for the reamers. I'm in the process of putting in new guides. The exhaust guides are sized correct but the intake guides appear to be sized a few thousandths smaller than the .342 minimum.

Thanks,
Warren

We ream the intake guides to .342, the exhaust guides to .343.

[WCarlsrud]

Thanks Charles. I finally bothered to open the engine maintenance book to actually 'read' the specs on the reamer tools. Now I just need to find some high-quality, yet resonably priced hand reamers...
So far Goodson seems to have some US Made HSS reamers for $42.99.

Hey, DAP.

This engine that I'm working on is the one that I got with the ambulance. Apparently the prior owner put in new rings, bearings, and a valve grind but they never replaced the guides <roll eyes>. The #3 and #4 exhaust guides were so worn out I didn't need a dial to determine that they were out of spec.

The ambulance is still sleeping in the woods waiting its turn.

This engine needs to get put back together in time for the power wagon rally in SC May 1st...