stopping oil/coolant? leaks

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
Ok, I know everyone is going to post check valve covers and intake...been there done that and corrected (removed and resealed the intake and dizzy then tested with dye. Also replaced Valve cover gaskets and tested with dye).
Now here is where we are at.
Engine:383 stroker (Prior to assembly the builder had the block Thermal cleaned, mag tested, bored and honed to 4.035 with Torque plates Hellfire finish) Diamond Pistons 6" Scat H rods, Supercharged, AFR 220 Competition heads All Fel Pro Gaskets and ARP hardware.
I have poured in some dye and verified oil is leaking from 4 areas where the AFR 220 heads meet the block. They are on the driver's side under the head bolts near the second and third spark plug and on the passenger side near the second and third spark plug plus at the rear of the head where it meets the block.
The verification of the leak at the rear of the head was to tape a small white paper towel to the cylinder head and block. Only the underside of the paper towel showed evidence of oil and at the seam only not on the top.
After chasing down all the oil leaks and curing them. I then drove the car and my Spal fan controller stopped working (failed in the off position) I had over heated the engine for about a block or so. Thinking I had blown a head gasket but I have removed the heads (and am sending them to be inspected and decked as needed) but I cannot see any damage to the head gaskets.
I am wondering what head gaskets are recommended. Fel Pro 1043? Fel Pro 1003? Fel Pro 1142-026 MLS?


Obviously step one is locating the source of the leak and that can at times be rather difficult.
please forgive these question's, because I know youll think are stupid, but I'd need a direct answer, as Ive dealt with similar issues in the past
(are you sure its OIL and not coolant?)
(are you sure the oil pan , timing cover,or front or rear seals are not leaking?)
keep in mind theres zero pressurized oil flow passing between the head gasket block and heads mating surfaces. all oil entering the heads is routed through the push rods and drains by gravity back to the lifter gallery.
A-ENGINE-OIL-02-small-block-v8-lub-sys.gif

265_oil-2.jpg


afr%20heads%20004.jpg

some cylinder head and engine block castings and some blocks that you might assume are compatible may not have the correct configuration to seal correctly and at times its not this obvious


potentially related threads

http://garage.grumpysperformance.com/index.php?threads/basic-info-on-your-v8-lube-system.52/


http://garage.grumpysperformance.com/index.php?threads/blow-bye-and-breathers.10646/

http://garage.grumpysperformance.com/index.php?threads/tracking-down-an-oil-leak.1430/#post-3168

http://www.themechanicdoctor.com/replacing-faulty-head-gasket-ultimate-guide/
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http://garage.grumpysperformance.com/index.php?threads/which-sealant-goes-where.700/#post-43768

http://garage.grumpysperformance.co...venting-leaky-head-bolts-studs.50/#post-12528
 
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Thank you, and yes I am positive and no there is no oil and water cross contamination or coolant leakage. That is the nice thing about tracer dye as you can see exactly where the leak is and that it is oil especially with the car on a lift. The dye under a black light leaves a tell tail trail from where it originates. Just to be sure I checked then cleaned all surfaces with Acetone and ran the engine again with the same results of oil coming from the exact same areas.
Anyway, I just got off the phone with Fel Pro tech support and the tech stated with over heating you get head shift and bowing (regardless who's Aluminum heads you are using) and the result will be oil seepage and distortion on the compressed rings. He had me look at the gaskets I removed and yep the rings at the ends (outer cylinders) were visibly distorted.
He recommended I have the heads inspected and resurfaced with a >30 Roughness Average then run an MLS gasket model 1142 installing them using Permatex Hi Tack on the block side and RTV at the intake corners (the dog legs do not go all the way up on MLS gaskets).Well I dropped the heads off at JGM and spoke with the tech and yep he agreed with everything the Fel Pro Tech said. He examined the head gaskets and confirmed that what the Fel Pro tech had said. He went on to say this is actually more common than you may imagine especially with Aluminum heads on an iron block. He also agreed with the suggestion of using Fel Pro 1143 MLS head gaskets and to spray Permatex Hi Tack on the block side prior to installation along with a dab of RTV at the dog ears up to where the intake will mount to ensure seal.

Net problem I have is trying to loosen the Shaft rocker valve adjuster jam nuts. I have tried and they just do not want to loosen. The adjuster is a 5/32" allen and the jam nut is a 12 point 7/16". I have even tried a socket allen and a long 7/16" wrench for more leverage to no avail (and I have tried several of them and they are all that tight). Being concerned I would break something I spoke with Crower and they said they should loosen right up. He suggested applying some heat to the nut to get it to expand.
This is weird, I have never had this problem before.

well, it seems youve located the oil leak issue ,
and its the result of over heating the heads and them warping as a result.
 
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