12V71N Heads, Rebuild or Take Chances?

[Freebird]

I just got a progress report from my mechanic yesterday. Everything is well on its way to being disassembled, and the heads are off my starboard.

He expressed a bit of surprise at the quote he got for rebuilding the heads, about $3,000. He informed the machine shop he could buy new remanufactured heads for a few hundred dollars more. Wonder what my old heads would be worth or if that figure was based on cores being available? Oh well, I'll ask that question of him.

My question for you guys is should I bite the bullet and go for a rebuild or new heads, or should I just have the mechanic examine them for obvious problems, take my chances, and use the three grand for other things?

 

[Genesis]

I would buy the Reliabuilt+ heads. You get a warranty and that's worth the few hundred bucks.

The price you're being quoted on the machine work must come with some knowledge as to what needs to be done - that is, I'd expect they need some significant work for that kind of coin.....

 

[thoward]

Do it right and you will not have to worry for many years to come.....

 

[Paul45c]

Ditto on the Reliabuilts -- that's what I did on my little sixes. Knowing your ADD problem with boats, there's a good chance old Freebird comes up for sale after a few years, and that would sound better to me sounding out an old boat to see those heads on the repair invoices; I think in that case it would be worth more to you than just $300 or so.

 

[captddis]

Is the 3000.00 for one or both? The premium plus heads for that engine are about 3800.00 ea. If the shop knows how to do Detroit heads and uses all NEW valves , springs and keepers. Then I would be ok with it.You do get a 1 yr warranty with the Reliabuilt heads but they only pay labor if a DD authorized shop installs the heads. Dave

 

[Boss Lady]

You already paid for the labor to R&R them, get them done now, so in six months when you have a problem you won't have to do it then. $3,000 for both heads is cheap. Reliabilt will be $8,000 for two heads including shipping and the warranty is only good if one their recognized shops installs them. Make sure the mechanic makes detailed notes of the work done, so if you decide to sell you have something that explains the work done and the level of detail. Too many rebuilds just have a shop name and an invoice amount, which only flys with me if you fold the invoice into a paper airplane and launch it.

 

[CARL GUZMAN]

The way you drive (balls out ) you should get the warranty I like to take it slow so I'm fine either way Randy still dosent under-stand thies boats are really trawlers he still wants a go fast

 

[CARL GUZMAN]

Let me put it another way the engines have been rebuilt ??? what 3-4 -10 times how much do you think that thing is going to hold at cruies with all the extra weight that makes cruies more like full speed ... she can't take it long maybe 500hrs...

 

[Freebird]

My mechanic says the heads look okay, but he is going to check them out further. The machine shop hasn't seen them, so I'm not sure where their numbers are coming from unless there is just a standard procedure to rebuild the heads. What the heck is there to do besides check valve springs, seals, rockers, and valves? I can see machining the heads to make sure they are nice and straight, but what else accounts for all this money?

I talked with my brother tonite who took a lot of diesel mechanic stuff in trade school before he went to work for Continental Airlines in Orlando. He called a machinist buddy of his who is supposed to do some checking and let me know tomorrow. Maybe I should just get him to sneak out a couple of Pratt & Whitney's for me!

Sorry to ask a stupid question as I have not paid close attention to the make-up of the 1271's. Are their two heads per engine or four?

I really don't mind money well spent, but I don't want to waste it either.

 

[Freebird]

Let me put it another way the engines have been rebuilt ??? what 3-4 -10 times how much do you think that thing is going to hold at cruies with all the extra weight that makes cruies more like full speed ... she can't take it long maybe 500hrs...

According to the PO, these engines have never been rebuilt and have less than 1,000 hours on them. My mechanic says he can't see any evidence that this estimate is right or wrong.

Remember these are naturals. You can run the crap out of them as long as the cooling system is operating correctly. I've been told they should run 4-5,000 hours with no problems if they are properly maintained. TRUST ME, they will be!

 

[Boss Lady]

If it were my money, i would spend the extra $3K and sleep well. If you are majoring this engine I would go all the way and know exactly what I have. 1200, 2000, 3000 hours who knows, make it 0 hours and then you know where you are starting. Lack of oil affects everthing, I don't like to gamble on engines, been there, done that, won't do it again. They should magnaflux the heads and check for cracks as part of the rebuild. Parts are not cheap, and DD parts never are. Measuring clearances and fit are time consuming, read many hours of labor.

 

[Pascal]

"Sorry to ask a stupid question as I have not paid close attention to the make-up of the 1271's. Are their two heads per engine or four?"

i have the V71 service manual right here :-( one pair of heads on the V12... it's the V16 that uses two pairs.

 

[Paul45c]

Randy, I'm sure you're getting quotes on a total reman of the heads as a standard program. I guess it's possible that you could send them out to the shop, who could perform some measurements and tests and work with some of what you've got, but I agree with Chris -- you've spent all this labor $$$ to tear down to the heads, and that ain't cheap so finish the job. Would YOU want to know that the PO was at the threshold like that and didn't go all the way? All that rebuild money spent wouldn't much to me if I heard the same old heads were slapped back on. I'd treat it like an engine with at least 2500 hrs. on it, which might not be fair, but there you are.

I know, easy for me to say because it's YOUR money, but here's something that came from my own experience: when I first got my boat, the engine surveys showed a huge amount of engine cooling work needing to be done. Both motors had to be stripped right down to the heads with everything taken off, cleaned up, all hoses replaced, etc. It was a big job, and in hindsight I should have plowed through the rest of the way and done kits & heads. I was back in there a year and half later doing it, anyway. If I'd have known how much of that labor would have been redundant those years later to get to that level of teardown, I would have finished the job then and there.

 

[ThirdHatt]

I agree, go with the reliabuilt heads with warranty. Especially since you run these engines at only 200rpm off the top. I know, I know Detroit's manual says this but everyone on here knows that 350-400rpm off the top is the most Detroits should be run at for good service life. If you run 'em that hard, you had better not cut ANY corners during rebuilds. Just my $.02.

When I bought my boat it had 177hr rebuilds and from learning so much on this forum I knew to be suspicious of such low hours. I inspected the invoices for the engines VERY carefully. When I saw listed that both engines got NEW Detroit heads, I felt much better. When I saw the invoice for four NEW turbochargers, I felt much better. When I saw that every hose on both engines had been swapped to the nice blue silicone hoses, I felt much better. These little things make a huge difference in the actual quality and perception of a quality job to a future owner. Knowing you, that guy may be looking over your invoice in the near future! DO IT RIGHT and it will pay off later!

 

[jim rosenthal]

Buy whatever has the best warranty. Hopefully you won't have to use it, but it will be there. If you have the heads rebuilt, and something goes wrong, you then have to take the failed part back to the people that did it- in whom you will have no confidence. I can't imagine a worse scenario, frankly. Get something where if it fails they give you a new one. You already have enough headaches with this motor.

 

[Freebird]

Gentlemen, please accept my apology for venting unrelated frustrations on this thread. If you are interested in the reason why, check out the opinion forum.

Thank you for the additional input. I'll keep you posted on the progress.

 

[Freebird]

After a lengthy telephone conversation with my friends, Paul Ludwig aka Paul45c and Chris Powell aka Boss Lady, some interesting points were brought up that I had not considered.

I had questioned why the heads would have been damaged since they circulate no oil, and my problems seemed to have been oil related.

Paul brought up the fact that on a boat that has sat idle most of the time, corrosive salt air could be introduced into the heads through unplugged exhausts.

Chris agreed this can be a problem. He reminded me that if I went with rebuilding my currents heads, they would still be over 30 years old. The new heads would be just that, new. I ***ume there have been some design improvements since the original heads were installed that would benefit me as well.

Not bad for a couple of "Black Sheep" huh? Thanks guys, I think I'm on track now.

PS SOMEBODY replaced my *** with asterisks.

PS again, As soon as I typed the word "***" it got corrected. Are we down to that now? Computerized censhorship? I can't even use the word "***ume" without being censored? I'm outta here.

 

[Ron Childress]

Re: 12V71 Mr Pascal

I have a manual for v-71 highway vehicles. Is this the same manual for the marine engines? I don't think so. What would you charge me for a copy of your service manual on the 12 cyl version, please?

ron.childress@power.alstom.com I can send you a fedex pkg with a free return envelope therein.
Thanks,
Ron

 

[Tawney1]

Freebird,

Covington Diesel in Wilmington is ready to start the rebuild on our 12-71Tis. I am told that reliabuilt heads are backordered more than 3 months out. We have settled on the option of having the existing heads rebuilt by a shop Covington is recommending.

If you are getting new heads any time soon, what is your source?

Thanks,
Paul