| Author |
Message |
Paul Newman (Newman)
Member
Username: Newman
Post Number: 397
Registered: 12-2001
| | Posted on Saturday, August 31, 2002 - 9:11 pm: | |
The seals are from an M5 bmw. You can bring an old ferrari one to match up. The dimensions are the same but they are made of a green rubber like material with a spring around the stem seal for a tight fit. They have a steel shell in them with rubber lining it to grip the guide. I drove them on with a deep 7/16 socket. I believe they are viton or something like that. They wont go hard and they work so much better than a factory seal. Its not my idea so I cant take credit. It was suggested to me by a private ferrari repair shop. I also hate the piston/ring setup. It sucks and is behind the times for sure. 3 compression rings and an oil ring? thats nuts and only adds friction and weight. I replaced my pistons with a set of forged custom 3 ring light weight ones(higher compression), 100 grams lighter than the originals. Like I said, no oil consumption and its seen 7800rpm many times. I would say the biggest cause for these old 308's to use oil is the top end. No doubt. Im surprised the guides wear out though with leaky seals and minimal side loading from the direct acting cam buckets. Dont forget to get your valve shims from volvo, an old 242/244/245 takes the same shims and I paid $3.70cdn each instead of $20 from ferrari. |
magoo (Magoo)
Advanced Member
Username: Magoo
Post Number: 3082
Registered: 2-2001
| | Posted on Saturday, August 31, 2002 - 9:11 am: | |
In my opinion, and as it seems to be the case, on the repairs discussed here on the F.C., the lower end of the 308 engine seems to be everlasting. The upper end, the guides and seals seem to get about 50 to 60,000 miles on them and they are due for replacememt. I also agree with Paul that a alternative seal should be used. There has been discussion about valve guides and what kind to use for better wear. Some of the guys have replaced the guides with the orig. ones and I think Nick Scianna has a different guide and seals he uses when he reconditions the heads. Check the archives there was a lot of discussion about this. |
billy bob (Fatbillybob)
New member
Username: Fatbillybob
Post Number: 24
Registered: 8-2002
| | Posted on Friday, August 30, 2002 - 11:21 pm: | |
Paul this was a nice idea. How did you come up with it? Is a Seal is a Seal is a Seal? I do hate those OEM Ferrari seals. I don't like their rings eaither. |
Paul Newman (Newman)
Member
Username: Newman
Post Number: 393
Registered: 12-2001
| | Posted on Friday, August 30, 2002 - 6:55 pm: | |
Im digging. |
David Jones (Dave)
Member
Username: Dave
Post Number: 279
Registered: 4-2001
| | Posted on Friday, August 30, 2002 - 3:28 pm: | |
Paul, If you could dig up that info I would sure appreciate it... |
Paul Newman (Newman)
Member
Username: Newman
Post Number: 391
Registered: 12-2001
| | Posted on Friday, August 30, 2002 - 2:15 pm: | |
Ben, it wont hurt to put seals on it and I would try that before tearing anything apart. Time consuming but worth the effort. The factory seals are as hard as a rock from new and are crap. I used a soft bmw guide seal on my 308 2v and I have NO noticable oil consumption whatsoever. I never have to add oil and Ive gone 4000kms on an oil change. The seals are from an 85 M5 I believe. If interested, I will dig deeper to get exactly the model and year, let me know. |
Mitch Alsup (Mitch_alsup)
Junior Member
Username: Mitch_alsup
Post Number: 132
Registered: 4-2002
| | Posted on Friday, August 30, 2002 - 2:01 pm: | |
Before speculating on whether seals would fix the problem, its likely time for a leakdown test. This will identify if the rings, valves, and guides are good enough to justify only doing the seals. |
magoo (Magoo)
Advanced Member
Username: Magoo
Post Number: 3080
Registered: 2-2001
| | Posted on Thursday, August 29, 2002 - 11:24 pm: | |
Ben, How many miles are on your engine? |
David Jones (Dave)
Member
Username: Dave
Post Number: 259
Registered: 4-2001
| | Posted on Thursday, August 29, 2002 - 2:38 pm: | |
Depending on the miles, replacing valve seals is common, but then so is guides... |
Ben Millermon (Brainsboy)
New member
Username: Brainsboy
Post Number: 42
Registered: 5-2001
| | Posted on Thursday, August 29, 2002 - 11:19 am: | |
I have an 81 308-2v and it smokes a little bit. Im thinking that replaceing the valve seals will cure the problem. Is it common for the 308 valve seals to go bad? Is replacing the seals a common fix or will there be any unexpected things like worn valves or valve guilds that cause the seals to go bad to begin with. Im not looking for someone to diagnose my problem, im looking for an outlook of what to expect when I goto replace my seals. |