Hey Guys/Gals, I'm about to embark on the Second major service for my 355. I've got 12,000 miles on the clock. My engine shows absolutely no signs of valve guide issues, however, my research says that they tend to fail around the 15K mile mark. I bought the car 5 years ago and put 6,000 miles on it in those 5 years, so I would imagine that I will put another 6,000 miles on it in the next 5 years. I'm leaning towards replacing them proactively. What do you think??
Yep. if you want to be proactive, when doing the major, check and see what guides you have. If you do have the original (problem guides), then you can consider if you want to replace them.
Not all sets of valve guides were bad. Some batches were good, some bad. No symptoms, no need to change. Do a leak down check during the major if it will make you feel better.
When you do your major and the engine is out. It is very easy to check them. If they are OK, leave them alone. Dosnt matter which guides were installed. Its not so much the material as the way they were installed and how much play they had then.
Do a leakdown for sure, if anything is suspect pulls the heads while the engine is out and get a good looksee
I think it would be prudent to do a leak down as others have mentioned as well as a compression test. Also, any other tests of engine health and performance that can only be done with the engine in situ. There was a recent thread (or recently resurrected) where an owner had to have a major done twice because the first shop did not properly diagnose something related to oil pressure and the test couldn't be done with the engine out. To me, this is an insurance calculation if there is no evidence that there is an actual problem with valve guides. $X now to avoid $Y expense of a valve guide problem develops during next major service. I think X = $3K and Y = $10K-$15K
mine failed at 17k miles on my 95 355 Bobileff was kind enough to replace the guides for me before it was shipped. However I wouldn't bother if it doesn't need it.
If a 355 has over 30k or just under 30k mikes, and had NOT done the valve guides .... Is it safe to say that it's good to go?
good question I just talked to my Fcar mechanic who's been doing this for 25+ yrs.....said he's only seen 3 355's in his history that had the valve guide issue. He did say that the 98-99MY hasn't produced any to his knowledge.....
My 355 is an early '95 model. Production in Aug '94. I'm definitely going to do a leak down test and a compression test. From what I'm hearing, the sentiment is to leave them be if there are no signs of failure. Just in case I do leave them alone and they do end up leaking oil into the combustion chamber, how long can the car run with bad guides? Will going 2-3 years do any damage, or is it something that should be addressed immediately?
My '95 had all of the guides replaced in February of '02 with 14,000 miles on the clock at Ferrari of Denver. So I would guess that if there is a problem, it occurs in lower mile cars. If the engine is already out, (other than the slight extra cost) why not replace the guides if they're bronze? Doing this preventative work will give you or any prospective buyer (if you ever decide to sell), a known solid point about the car rather than guessing or worrying - and it may be worth more to that buyer. It was worth a premium to me when I purchased my car. I believe Luke (355dreamer) had them done on his '95 White 355 GTS that sold at a top price - so yes, it can add to a selling price. Robb
