Quote:
Originally Posted by RodKnock
First you said FE's have reliability problems, then they're prone to oil leaks, unless built by the top builders in the country. Yes, my FE doesn't leak and hasn't had any reliability problems and I'm sure there are quite a few others on this forum with reliable leak free FE's.
I've had SBF's and BBC's with leak problems. There was just a thread on here about new Ford 427's (SBF) with valve seal issues and leaks. I just think you can't use some all-encompassing large generality about any engine, especially with the parts and technology available in 2011-2012. |
Reliability problems, unless built by a pro.
Oil leaks even when built by the pros. Again the design requires more skill to build than the average design.
Here are comments from a 2007 thread on this forum about an
oil leak problem by two top notch guys.
Written by Keith Craft 5/10/2007:
I can not see an engine builder taking an engine that is running perfectly fine back because of an oil leak on a used block. I tell everyone that gets a FE engine do not be surprised if it leaks at the rear main seal. I have built enough of the new and old ones to know. We have tried evrything that we can find and since we do not make the block or machine the seal area we can not stand behind rear main seal leaks. We do check them on the dyno and if they leak we do all that we can to fix them. We have even gotten Chrysler Big Block rear main seals and worked on them for the blocks that seem to be a little big in the rear seal area and have had some suddes doing that in bad situations. It is not only the size of the seal area it is also how it is machined in relationship to the center of the mains. We machine the early 302 and 351 blocks that we do for a one piece rear main seal and find the original two piece seal area of center as much as .030 and it is hard to seal up something that is that much of center. The blue prints for the origins FE engines had most of the tolerances at a plus or minus .025 for areas like this. Even the lifter bores are listed with a plus or minus .025 tolerance for their location. This means that you could have one bore plus .025 and another minus .025. This is mone reason the factory used a rope seal. I have not been able to find any rope seal of late and then they had their own problems. I have had this with all of the original and new FE blocks. You can not machine these blocks for a one piece seal because of the size of the flywheel flange and bolt pattern. Now if we had cranks made with a small block bolt pattern and we could get flywheels with a small block bolt pattern with a 184 teeth we could do this. Maybe I need to look into a new way to go and any ideal would be nice. If I get a FE engine that runs good and is giving me no problems and only leaks a one to two inch circle after setting over night I am happy. Good luck, Keith Craft
The next post by Barry R. (I don’t want to butcher the spelling of his last name):
Amen to that!
I spend way too much time trying to get the rear main seal "perfect" - using a variety of chemicals and such. And I still get a leaker from time to time.
I think an FE is the only engine that you assemble with nails...
I cannot really comment on the amount of leakage or the reasons - that stuff is nigh unto impossible to isolate sometimes even with the car in front of you, much less over the internet.
Five posts later by Keith Craft:
I try to talk about all of the pros and cons to an engine build. As I said earlier when it comes to FE engines the rear main seal is always discussed. We do not have many that leak but every now and then we do. We have spend more time on oil leaks and rear main leaks in the last couple of years than we have making HP. What I mean by that is that the HP is not a issue on these engines and the oil leaks are. We have worked with all sorts of products and methods to try and come up with a full proof method but we still have not got one. If I put 100 engines on the dyno built the same way they will all make the HP they should but we will have a few that will leak. This is what I mean by spending more time working on oil leaks. With the CNC equipement we use on the heads and blocks along with our years of racing FE engines the power is a non issue but that damn rear main seal is still lerking waiting to leak. It really sucks that is for sure. Keith
I feel my comments were objective and fair. You make good points that all engine designs have their problems. 2007 is near 5 years ago maybe thing have improved.