35 Super 8 head gasket

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dfs
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Joined: Mon Nov 23, 2009 9:42 am

35 Super 8 head gasket

Post by dfs » Tue Sep 21, 2010 5:09 am

35 Super Eight with Stromberg EE. Sat idle for a year, was my father’s car. Must move into storage within a month. Cleaned carb, removed and cleaned plugs, squirt of oil in each cyl. Oil dipstick did not show any water or separation. Added a pint or two of antifreeze to raise level up into filler neck. Restarted easily, but, white exhaust, some at idle, more at higher rpm. Ran about 20 minutes, thinking maybe I was burning off Marvel Oil. Still white exhaust cloud and so I shutdown.

I remember years ago when the head gasket was blown and antifreeze was spitting out the tailpipe. Eventually, engine was completely rebuilt. Splatter not seen this time, a paper towel at the exhaust did not pick up any moisture (maybe meaningless).

Removed the plugs, black dry carbon on all except #8 which had a slightly shiny oil smear on the electrode. I blew air into each cylinder to see if moisture would splash out, not detected. Sealing with a rubber cork and 60 psi air through the cork, each cyl appeared to hold pressure. Listened and watched at radiator for air sounds or bubbles, not detected.

How to further or better investigate possible/likely head gasket leak? Retorque head? One stud may be loose in block and has small weep of antifreeze. Could oil still be burning off (white?) from the long sit? Keeping me awake - will I be driving or towing into storage?

Thank you,
David

Dave Czirr
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Re: 35 Super 8 head gasket

Post by Dave Czirr » Tue Sep 21, 2010 5:33 am

You've done a good set of diagnositcs, my suggestions. First, attend to the loose stud is indeed it's loose. As long as the threads in the block are undamaged, you can sometimes remove and replace it with the head in place, or simply tighten it (put a bit of sealing shellac on the block-end threads). Then retorque the head (about 62 lb-feet) and take a compression test to see if #8 shows low compression (blown gasket?). Start it up and reevaluate.

White smoke is not from burning oil, it's almost always steam for water in the combustion chamber and if from a small leak in a head gasket it usually clears up with a few minutes of running, only to begin again after the engine has sat static for a while.

There are other possibilities for the steam in the exhaust. If you look at where the exhaust manifold mounts to the block, you'll note that the manifold branches at least on the Eight just overlap some of the block core plugs (so-called freeze out plugs). If one of them is loose or perforated and leaking, it can leak into the exhaust manifold and create a rather continuous steaming at the tailpipe. This actually happened to me in my 34 Eight and had me baffled for a time. Your test with the cork and compressed air may well indicate the absence of a crack in the block, but perhaps if the compression test is inconclusive, a more sophisticated cylinder leak-down test might be in order.

Please, keep us posted.

dfs
Posts: 9
Joined: Mon Nov 23, 2009 9:42 am

Re: 35 Super 8 head gasket

Post by dfs » Tue Sep 21, 2010 8:52 am

From memory, the questionable stud is between and maybe in line with plugs 6 and 7. Thinking of removing acorn nut and checking whether stud is tight or spinning. Maybe the stud will come out with acorn nut? Would I leave other head bolts tight?
Thank you for the quick reply. Greatly appreciated.
David

Dave Czirr
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Re: 35 Super 8 head gasket

Post by Dave Czirr » Tue Sep 21, 2010 9:19 am

Yes, leave the other headstuds/nuts tight. The stud may or may not come out as you loosen the acorn nut. If just the nut comes off, you usually have just barely enough room to jam 2 7/16-20 nuts against each other (you might even have to thin them down a bit) and use them to tighten the stud if necessary but if it's really loose, I'd recommend removing it,checking the threads, and using some thread sealer before reinstalling. Use of a conventional stud-tightener or installer probably isn't a good idea because they are meant to grip on the shank of the stud and will bugger the threads.

dfs
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Joined: Mon Nov 23, 2009 9:42 am

Re: 35 Super 8 head gasket

Post by dfs » Thu Sep 23, 2010 4:53 pm

35 Super Eight stud size? I know 7/16-20 one end, and what should the length be? Any chance they would be an off the shelf part?
Thanks.

Dave Czirr
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Re: 35 Super 8 head gasket

Post by Dave Czirr » Thu Sep 23, 2010 4:58 pm

Studs readily available from the usual Packard vendors in full sets, don't know if they sell them individually. I'd NOT recommend anything other than the correct stud. If you try Kanter or Max and they won't sell a single, I believe I have a coffee can filled with old but good ones, let me know. If I can find them, you're welcome to one or more.

dfs
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Joined: Mon Nov 23, 2009 9:42 am

Re: 35 Super 8 head gasket

Post by dfs » Fri Sep 24, 2010 4:55 am

Thank you for the offer. I'll be searching the hiding places in the shop this weekend, maybe will find one. Hope to at least determine if stud is broken and extract if needed. On the positive note, I was reminded that the car was running and NOT steaming when put away over a year ago.
Best regards,
David

dfs
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Joined: Mon Nov 23, 2009 9:42 am

Re: 35 Super 8 head gasket

Post by dfs » Mon Sep 27, 2010 8:54 am

Good news/bad news.

Retorqued head, a few acorns tightened up. Confirmed stud #17 between plugs 7 and 8 was not tightening. With jam nuts and some upward force, was able to unscrew stud. Stud not broken, good news; threads in block are stripped, bad news.

Able to hand tap into block and feel some grip from threads, but sloppy. Cleaned up threads on stud - clogged with bits of cast iron from block.

(Noted the starting threads on stud were deformed, maybe this was cause of block threads stripping, not important now. Looks like maybe 4 or 5 threads are all that are engaged in the thickness of block - typical or could the casting be thin in this area?)

Applied stud epoxy to threads and reinserted into block. Torqued stud a bit beyond hand tight and left to cure until next chance to work. Maybe I can get some torque, better than the zero it was at, and test run engine.

Removing head and installing helicoil would be the right thing to do, but I must get car into storage soon. Thanks for your help. I'll hope to report progress by next week.
David

dfs
Posts: 9
Joined: Mon Nov 23, 2009 9:42 am

Re: 35 Super 8 head gasket

Post by dfs » Tue Nov 09, 2010 9:26 am

"Next week" almost turned into famous last words, I am grateful to be able to reply. The repaired stud did not hold, but retorqued head, even with one stud missing, resolved the white steam and car ran well when driven into storage. Thanks again for help, David

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