Aluminum blocks and oil leaks....

[CliffBeer]

Just wondering what has been folks experience with SBF aluminum blocks and oil leaks....? I've found most all aluminum engines (porsche, ferrari, alfa) to be pretty prone to oil leaks and I'm curious to find out if the alloy block engines exhibit a materially higher rate of oil leaks than the non-alloy blocks.

Thanks in advance.

 

[roaldin]

I have several Aluminium engines, including a SBF, and none of them leak.

Tim.

 

[Steve Briscoe]

Cliff -
My experience is that you're right. Everyone I've had or seen (4) leaked a little. Maybe I was just unlucky. Saw another one last week with a friend's Porsche up on a lift. Super nice car but had some minor leaks here and there. I've been talking to Roush about the aluminum block option on the SBF and this thread will be helpful to see if the design of the American V-8 somehow eliminates leaks. That would be my preference because if one pays an additional 3K for an aluminum block, it would be good to know leaks are not inevitable.

 

[Ron Earp]

There are millions and millions of all aluminum engines in cars all over the world. If they had a leaking problem due to aluminum I'm sure Honda, Toyota, etc. would know about it. Motor cycle engines have been all aluminum for 30+ years and don't leak. At least none of the many I've had leak. I don't buy "aluminum leaks" because it is aluminum.

I imagine the leaking from the Porsche/Ferrari/rare camp has more to do with less money, drive, or consumer force for them to spend on proper seal design and using older engine designs, than it does on the the construction material.

Toyota can redesign the upper flange of a cam tower to seal better from one year to the next, I doubt the others do that. Toyota could also force the seal manufactuer to change a design quickly, or to eat some costs in the case of an issue. I doubt a manufactuer that is taking 5000 a year from Felpro has much clout over one that is taking 1,000,000s from Felpro.

Emperical evidence suggests it simply isn't the case that aluminum engines leak because they are aluminum.

 

[Ian Anderson]

Unless it's a Rover V8 then I've been reliably told they stop leaking when the oil runss out!

Ian

 

[Ron Earp]

Oh! And I forgot our beloved racing TR8 all aluminum motor - none of the three that have been in there have ever leaked a drop, and we build them!

R

 

[Russ Noble]

Oh! And I forgot our beloved racing TR8 all aluminum motor - none of the three that have been in there have ever leaked a drop, and we build them!

R

That's the answer Ron! Do it yourself and do it right.

There is absolutely no reason why a properly designed engine with modern seals carefully assembled should leak oil. However, I hate pressed steel pans which tend to distort and need a lot of care to prevent damage and subsequent leaks. I much prefer cast aluminium pans which are much more rigid and have nicer sealing surfaces.

Pommie cars, and particularly bikes have always deservedly been the butt of oil leak jokes. Iron and aluminium alike, but this is invariably due to totally crappy design and inferior seal technology.

Even good seals deteriorate over time and unless you're extremely pedantic and have nothing else to do, replacing them is hardly worth the hassle, or if you're paying someone to do it, the expense. IMHO.

Maybe the Ferraris and Porshes Cliff is talking about are a little older anyway? There are alot of these type cars out there that are older. Ordinary cars become unloved or scrapped long before exotics so nobody cares about their developing oil leaks!


Cheers

 

[Andy Besic]

I've never seen an Alfa Romeo that didn't leak.....I always thought of it as Italian undercoating

 

[Keith]

Cleverly, British built cars were DESIGNED to leak oil whether Ali or Iron lumps. The reason was simple. The steel we used in the car bodies was such complete crap and they didn't want to waste any money on anything as high-tech as galvanising or underseal so the answer to stop it rotting in it's first year was quite simple and very cost effective!

 

[CliffBeer]

There are millions and millions of all aluminum engines in cars all over the world. If they had a leaking problem due to aluminum I'm sure Honda, Toyota, etc. would know about it. Motor cycle engines have been all aluminum for 30+ years and don't leak. At least none of the many I've had leak. I don't buy "aluminum leaks" because it is aluminum.

I imagine the leaking from the Porsche/Ferrari/rare camp has more to do with less money, drive, or consumer force for them to spend on proper seal design and using older engine designs, than it does on the the construction material.

Toyota can redesign the upper flange of a cam tower to seal better from one year to the next, I doubt the others do that. Toyota could also force the seal manufactuer to change a design quickly, or to eat some costs in the case of an issue. I doubt a manufactuer that is taking 5000 a year from Felpro has much clout over one that is taking 1,000,000s from Felpro.

Emperical evidence suggests it simply isn't the case that aluminum engines leak because they are aluminum.

Ron, respectfully disagree with you wholeheartedly here. If you'll bear with me for a minute you'll find that there are distinct reasons why aluminum block engines are more prone to leaks. Some basic points:

1. True, just about any engine can be made not to leak, including aluminum engines. Just takes money and engineering.
2. Similarly true that aluminum engines are most certainly more prone to leaks than iron block engines. Why? Any good automotive engineer understands that the thermal properties of aluminum are vastly different than iron. In one (of several) significant respects, the aluminum expands and contracts much more than does the iron - on a magnitude of 2X or 3X (rough numbers). This continual expansion and contraction through the heat cycle of the engine a) makes it more difficult to seal aluminum, and b) wears out gaskets much more quickly because they are constantly walking all about the mating surface.
3. The above (2.) problem can be fixed with engineering solutions, and, companies like Honda and Toyota have done an admirable job of this on their aluminum block engines. Not all companies have been this successful in this regard. For example, I would suggest that porsche and ferrari and alfa are in this latter camp generally speaking.
4. The issues isn't simply "do all aluminum engines leak"? Obviously, this is not true given the admirable sealing of Hondas, Toyotas, etc. The issue is more refined than this, namely, to what degree is the alloy SBF block inclined to leak (if at all) and what characteristics does it exhibit in so doing? Secondarily, another line of inquiry would be to what degree do SBF alloy blocks vary among mgf's and are some better than others in this regard.

Hope I'm helping to put a finer point on the point of inquiry here. I have lots of experience with many different alloy engines, just none with SBF so I'm posing the question now to this group because if anyone knows it will be this bunch of smart fellas!

Thanks!

 

[Ron Earp]

Cliff I think we are saying the same thing.

You indicated your felt "most all aluminum engines (Porsche, Ferrari, Alfa) to be pretty prone to oil leaks". I don't think it is because they are aluminum. I think it is because they are poorly designed, or poorly made, or poorly machined, and/or they use gasket designs that were not good because of their low volume production and relatively small R&D efforts. A properly engineered engine will take materials into account in the design so that the product won't leak.

I know my Lotus 9XX engines have all leaked. And it isn't because they are made of aluminum, it is because Lotus didn't have the R&D team, time, or money to properly design it so it wouldn't leak. Mine likes to mark territory, at least that is what I tell folks.

But to focus on the question: I don't think an aluminum SBF will be any different from an aluminum Buick 215 that we build, and modern gaskets make that little motor seal up tight. I haven't heard of anyone having problems with iron block and aluminum heads that are so common on SB Fords now either (and many more old iron block aftermarket ally headed Chevys around) I've built a bunch of ally headed iron Ford and none have leaked oil. They seal up tight and in theory should have more trouble than an all aluminum design due to the differences in expansion of materials, but that doesn't seem to be the case.

 

[Sandy]

Yes, only british aluminum engines leak, had to replace the leaking oil pan on an Aston v12 with < 1200 miles, and yes, now it only leaks as prescribed in the operating manual for all english cars...

For the Alum SBF (Ford SVO) in the mustang, the only leaks in 2 builds of the motor have been some rear main weep, but nothing that has dripped on the ground yet. Older blocks with the rope seal are much more prone to leaking then the newer one piece in 5 oh blocks and SVO, but they are not fool proof either... Well, I lied, I had another leak, the dipstick came up an inch at the track and sprayed oil like a fire hose...

Good assembly practices, good gaskets, good (as in correct for the application) sealants for the job solve most problems except for holes in the side of the pan!

Sandy

 

[Jac Mac]

Most of the leaks being discussed here are the result of poor assembly practice or a small design fault that shows up in use. The dipstick tube in a SBF is a classic. If Ford had simply positioned the dipstick on the other side of the timing cover the oil thrown from the timing chain & front counterweight would have gone no where near it! Two piece rear main seals need to be installed 1 up/1 down in relation to cap face, Prelubed with grease to prevent sticking and the knurl may need to be polished if to aggressive to avoid seal damage in this area.

I found out the hard way that on Toyota 4 cyl Diesels that if you dont use the 'Toyota' front crank seal it will spin in the cover, the aftermarket seal being of different construction/material just wont hack it. This did not happen straight away but about 15000/20000 km after fitting. The $50.00 saved on the 'cheap' gasket set was miniscule in relation to the time/$$ spent in replacement& new timing belt reqd.

Jac Mac

 

[Sandy]

Yep, the dipstick was a funny thing. Everyone knew about it when I opened the hood . Solved with a spartplug boot over the top of the dipstick that keeps it well anchored but easy to pull.

Sandy

 

[Jac Mac]

Yep, the dipstick was a funny thing. Everyone knew about it when I opened the hood . Solved with a spartplug boot over the top of the dipstick that keeps it well anchored but easy to pull.

Sandy

Great minds think alike---- except I use a sparKplug boot.---- or are you using 'smart plugs'?

Jac Mac

 

[John Fitzpatrick]

Cleverly, British built cars were DESIGNED to leak oil whether Ali or Iron lumps. The reason was simple. The steel we used in the car bodies was such complete crap and they didn't want to waste any money on anything as high-tech as galvanising or underseal so the answer to stop it rotting in it's first year was quite simple and very cost effective!

Thank God. I've owned and MG TD, a TR3, two XK-Es, and a Lotus 47, all of which leaked(although with the MG , "leak" was sort of euphemistic) and I always hoped it was an undocumented design feature of British engines, sort of like headlights going dark at speed was a Lucas feature. Massively relieved to know that it wasn’t a Kim Philby plot.

 

[Chas]

World Products/Bill Mitchell builds 420 crate engines annually. At least 25% are all aluminum. We are about to release our Man O'War Windsor version with 8.2 and 9.5 decks.
We have found that alloy blocks are not more prone to oil leakage than iron. We dyno test each engine before shipping and the primary cause of leaks are splits in the seams of, or pin holes in a manufacturers oil pan.
When a customer has oil leaks it is most often due to the customer removing our valve covers (with breathers) and replacing them with custom covers with no breathers. We have cautionary language in the instruction sheets against this but who reads instruction sheets? Right?
Always vent the crankcase in your favorite manner.
A major improvement in the battle against leaks was when we switched to "Right Stuff" sealant and gasketmaker.

 

[Sandy]

Great minds think alike---- except I use a sparKplug boot.---- or are you using 'smart plugs'?

Jac Mac

Your a funny man Mr. Mac The boot was a lot smarter that day in any case!

I did forget about 2 other oil leaks. One was in a canton pan that was a Pin hole at the edge of a weld behind the pan rail. Shot out like a squirt gun.

Then the Aviaid pan that lead from the bottom of the pan, another bad weld. But par for the quality that I have seen from them in the pick up as well (weld slag loose in the pickup)...

No problem yet on the Armondo pan.

One that that I live by when doing pan gaskets is NEVER use silicone sealer of any type. I hate it for the pan (especially BLUE). I know that I'll start a flame war but I don't think much of silicone in the pan area. I do love 3m Hitack (Yellow death/Snot) as my goop of choice for the pan, your mileage may vary.

BTW, Hope everyone has a nice holiday! Better check my spelling now

Sandy

 

[kent holst]

i am an pro modiefied drag racing mech and we run all alu ewerything and tear things apart every 2 nd run and have never had a leak we always use alu silicon from G E .very cheap very good fast drying .we by it at the HOME DEPOT

 

[Sandy]

i am an pro modiefied drag racing mech and we run all alu ewerything and tear things apart every 2 nd run and have never had a leak we always use alu silicon from G E .very cheap very good fast drying .we by it at the HOME DEPOT

Likely works well since you tear it down every other run .

The problem that always notices with the likes of permatex BLUE and some of the other generics is that after a while the sealant get bleached looking and seemes softer where in contact with oil. The 3M Yellow Snot is the worst to remove, but seems to stay put and not be affected by the likes of motor oils, again your mileage may vary...

Sandy