Topic: streaks on side of engine block

[tnguy624]

I have put a little over 1000 miles on my rebuilt 66 mustang 6 cylinder. Over the last few months I discovered streaking on the side of the engine block after coming home from trips out in the car. I repainted over the streaks for car shows but they continue to reappear. While letting the car idle for a period of time I can't feel any moisture in the area, so it must be happening while the car is running at higher RPMS while driving.

My initial thought is it could be coming from the head gasket, I do not have any antifreeze mixing with my oil, and  no loss of coolant. A mechanic told me it is probably anti freeze causing the streaks because oil would not dissolve the paint, but anti freeze would. I also have no loss of power.

MY thought is it could be that the head bolts were not torqued properly, and I plan to re torque them. I have attached a picture of the streaks and am wondering if anyone else has had this problem and  could let me know if my assumption of head bolts not torqued right could be the cause.

Thanks so much for any and all help with this!

Terry

[J_Speegle]

Head gaskets can do allot of odd things. In this case it appears (and based on your reporting) that they are working as a one way valve - allowing fluid out  (to the exterior) and not inward - lucky you. Guessing your not getting air from the compression cycle into the radiator/cooling system

Re-torquing might work but you likely looking at a new gasket. But give it a try - repaint the area and test

[NEFaurora]

Terry...

IT IS the Head Gasket leaking coolant.  The ONLY fix that works is below I have found over the years...and it works.

Follow these directions:

I have lots of experience with this one.... Been down this exact 6cyl road a few times. The ONLY way to stop leaking like this is to change the head gasket again with a Fresh FEL-PRO one, and make sure that the block side, and head side are both completely dry, and coat both sides of the Fel-Pro Head Gasket liberally with Permatex's HIGH TACK GASKET SEALANT - comes in a little jar. Lightly coating the head and top of the block is recommended also while staying away from any combustion areas.  Just coat any contact areas that will contact the new gasket, but pay attention to the coolant journal areas (the areas that are leaking on the left side of the engine.) Make sure that there is a good coating of High Tack Gasket Sealant there especially on the left side of the block.   On the Fel-Pro Gasket, It actually says "Use NO Sealer", but that is total BS.  It only says that because the gasket as-is, is supposed to take advantage of its Patented "Perma-torque" sealing...but that is total BS too because it never seals tight around the cooling journals..Hence your leakage.. With the contact areas and both sides of the gasket coated with Permatex's HIGH TACK GASKET SEALANT, Torque the head using the correct sequence, going 1st time, 60-65 pounds, then 2nd time, 70-75 pounds, then finally 80-85 pounds.   ***Very Important, Before torqing 6cyl head bolts, With the head off, Chase each of the head bolts first lightly with the bolt's threads coated with regular engine oil before chasing and torqing.

Happy Motoring!!

[Rsanter]

I agree with the above but will add the following....
Get new head bolts. Factory heads bolts were designed to give 2 reliable installed torques. After that is is a crap shoot. You can torque them in but they may be stretched already a little and will not hold the torque ofer time

Bob

[suskeenwiske]

To add to the above, be careful to not get too much oil in the blocks bolt holes; the hydraulic pressure that develops when tightening the bolts could potentially crack the block. Also, check that the block and head are true. If they are not, one or both may require machining to restore the surfaces so the two will mate properly. And again, as mentioned above, torqueing in the correct sequence and stages is 'ALL IMPORTANT'.

Ray

[tnguy624]

Everyone, THANKS SO MUCH! for your input and advice, I so much appreciate it.  NEFaurora, thanks for taking the time to explain in detail about the head gasket replacement.  Ray and Bob, and J-speegle  thanks for additional tips as well!

Terry

[tnguy624]

Thought I'd give an update on the streak problem, took the cylinder head off last night and found the source of the problem, actually it was a two fold one. There was no sealer on the head gasket and found that the head was warped also.

I had bought the rebuilt engine on e-bay 2 yrs ago and contacted the seller about my situation, he is rebuilding me a new head and is shipping it to me at no charge! If you are looking for an honest man with integrity for an engine rebuild I would highly recommend him! His name is Jeff and his name on on e-bay is 1hotvega.

Also again thanks to all for the tips, I did by new head bolts as suggested and will use all the other advice that was graciously given.

Terry 

[J_Speegle]

Thought I'd give an update on the streak problem, took the cylinder head off last night and found the source of the problem, actually it was a two fold one. There was no sealer on the head gasket and found that the head was warped also.........

Sealant on the head gasket Must be a new thing. Never have used anything but some silver paint then throw them on

Thanks for the up date it appears some of our thoughts were correct

[carlite65]

i think most of his problem was the warped head. i have never used sealer on any head gasket. never had a problem following the mfrs. instructions.

[NEFaurora]

On V8's yes, not an issue, But on a six-banger?  Almost all of the 200cid I6s leak on the left side sooner or later...  The coolant passages on the I6 are near the left side and rear of the block.  They almost always leak.  It's a big problem on I6's but controllable if you do it right.  A warped head has nothing to do with it.. You could have the head and block properly decked and it would still happen over time (within 2-3 years).  I would say it has more to do with the type of gaskets and location of the coolant passages so close to the sides.  If better designed gaskets were invented for the I6, It would cure the problem.  The Fel-Pro "Perma-Torque" self sealing gaskets do nothing to keep the head from leaking.  Fel-Pro needs to come out with a better sealing gasket maybe of a different type of material possibly.  The "Perma-Torque" self sealing gasket is a design failure IMHO because it will fail everytime to seal correctly without using somekind of outside "sealer" being used to cure the problem.  They just don't seal correctly on their own.  It's just that simple.  Anyone who has done enough I6 Head gaskets already knows this.  Terry's coolant leakage problem with coolant streaks on the left sides of the I6 block is highly typical.  To tell you the truth, I'm surprised that more people have not complained about the issue over the years.  Terry's head being warped is most likely a coincidence, though I'm not saying that it could not have contributed to his problem.  Perfectly straight I6 blocks and heads suffer the same "leakage" issue.

Tony K.