Front Cylinder Head Gasket Change.`

Post Reply
foundationapps
Member
Posts: 364
Joined: Tue Sep 01, 2015 9:26 pm
Bikes: 1948 Panhead
1985 FLHTC
2020 Electra Glide Standard
2016 HD Road Glide
Has thanked: 1 time
Been thanked: 14 times

Front Cylinder Head Gasket Change.`

#1

Post by foundationapps »

Good morning, hope everyone had a great Thanksgiving. My food coma is over.

KB had all the answers I needed on gaskets and techniques. Amazing source of information. I have an easy one I think tho.

Question, Had a front cylinder head gasket leak on the Pan. STD heads look great, after pulling the head, you can see where it blew around the 10 o'clock position (12 o'clock being the nose of the bike. That's the oil that leaked down into the generator.

James gasket kit, been reading the KB. Noting the metal ring in the James gasket, I know the head must be flat to seal. That's all good. Here is the question.

1. Rear cylinder is tight, no leaks, should I leave well enough alone? Or pull that head and change head gaskets at the same time.

2. I don't have the time resources to take this head to a pro to have it blasted and cleaned. Leaving the valves in. Can I successfully clean it at home in a solvent, scrape out carbon, avoiding the seats, blow it out with air and reassemble?


Respectfully
Bigincher
Former member
Senior Member
Posts: 2784
Joined: Tue Dec 18, 2007 2:10 pm
Bikes: 1941/59 EL
1952 FL
1977 FLH
1994 Fatboy
Has thanked: 22 times
Been thanked: 110 times

Re: Front Cylinder Head Gasket Change.`

#2

Post by Bigincher »

If it was mine, I would not change a head gasket that isn't leaking. "If it's not broken, don't fix it."
Sure you can de-carbon and clean up the head without disassembling it. The valves will be closed, no worries about the seats. Clean to your hearts content.
But something more concerning, what caused the head gasket to blow in the first place? Was it from a failure to re-torque properly?
foundationapps
Member
Posts: 364
Joined: Tue Sep 01, 2015 9:26 pm
Bikes: 1948 Panhead
1985 FLHTC
2020 Electra Glide Standard
2016 HD Road Glide
Has thanked: 1 time
Been thanked: 14 times

Re: Front Cylinder Head Gasket Change.`

#3

Post by foundationapps »

Makes sense about leaving well enough alone. STD heads, bored .020" over. I bought this bike from a guy that had it for 40+ years. The engine was rebuilt by a reputable and well established Panhead man. It did sit unrode for about 5 years due to health of the owner. I bought it and rode it a lot, 3000+ miles in 8 months, varying conditions.

Not a drop of leakage until earlier this summer. Just a small seep, then enough to contaminate the generator. Didn't seem to leak a lot, the chain is oiled by the auto-oiler, so what I periodically added made sense. After I smoked a dog in October, I tore the entire bike down to repair damage and change frames. That's when I decided to tackle the head gasket leak. After pulling the front head yesterday, that's where I spotted the leakage around the head gasket. It's a broad pattern, about 2.5" wide, nothing is Soaked. I have James gasket kit. The head gasket has a metal ring.

The 5 bolts all broke loose with what seemed like correct force. The front two "seemed" to be a bit looser, but not much. Hard to tell by feeling release force.
Andygears
Senior Member
Posts: 1396
Joined: Tue Feb 05, 2013 12:25 am
Bikes: 1950 panhead, 1999 FLHTCI, 1987 FLHTC custom
Location: Daytona Beach
Has thanked: 438 times
Been thanked: 648 times

Re: Front Cylinder Head Gasket Change.`

#4

Post by Andygears »

Bigincher wrote:If it was mine, I would not change a head gasket that isn't leaking. "If it's not broken, don't fix it."
Sure you can de-carbon and clean up the head without disassembling it. The valves will be closed, no worries about the seats. Clean to your hearts content.
But something more concerning, what caused the head gasket to blow in the first place? Was it from a failure to re-torque properly?
So it wasn't ridden for 5 years, then you ran it hard for 8 months, saw a leak and still didn't retighten? Anything? Enough oil to contaminate the genny must have been a bunch to seep in around the strap. Was the motor new before sitting for 5? Or had it been broke in & retightened by PO? At 10 o'clock the oil was from the return so compression pushed oil out. Did it pressurize the crankcase thru the return? Check the threaded holes in the head & clean to be sure the bolts are free to travel beyond where they were when assembled.

You say oil usage was caused by "auto-oiler" , what oil pump is on the motor? Could you have had excess pressure in the lower end, causing breather pressure and significant oil usage? Or...did the genny get contaminated from the crankcase excess pressure?

Become a detective, examine everything, replay different scenarios, learn from this and then this won't be the PO's bike, it will be yours!

My two cents
Andygears
talldrifter
Member
Posts: 67
Joined: Tue Dec 21, 2010 6:48 am
Bikes: Aftermarket Panhead in Shovel frame, 1978 XLCR Sporty in disguise
Location: Tennessee
Been thanked: 3 times

Re: Front Cylinder Head Gasket Change.`

#5

Post by talldrifter »

I noticed that you referred twice to "the metal ring" on the new James gasket. If you are not familiar with it, I will try to enlighten you from my understanding. James calls it a "fire ring" to prevent leaks. When you put that on and torque the heads, it has to fit somewhere, so it creates a dent in the aluminum head since it can't change the cast cylinder. Now you have modified your head and can look forward to buying more of the same in the future if replacement is needed. Whenever I have pulled my heads I notice that there is a "fire ring" as part of the top of the cylinder, I don't need two. An indie shop near me used them because they didn't want customers coming back for unpaid work because of a leak or whatever. As you can tell, I don't use them, I would use the blue ones not the fire ring type.
If I am mistaken in my explanation, anybody, please correct and enlighten me.
If you have a large flat file you can lightly run it over the head gasket surface to check for an uneven surface that might have contributed to the leak.
Bigincher
Former member
Senior Member
Posts: 2784
Joined: Tue Dec 18, 2007 2:10 pm
Bikes: 1941/59 EL
1952 FL
1977 FLH
1994 Fatboy
Has thanked: 22 times
Been thanked: 110 times

Re: Front Cylinder Head Gasket Change.`

#6

Post by Bigincher »

I agree, taildrifter. Panhead cylinders do have a 'fire ring'. It's a feature that makes them a better candidate for sleeving. Knuckle cylinders are not a good prospect for sleeving because they lack that feature.
I also like the blue James head gaskets, but I'm not a professional motor builder.
foundationapps
Member
Posts: 364
Joined: Tue Sep 01, 2015 9:26 pm
Bikes: 1948 Panhead
1985 FLHTC
2020 Electra Glide Standard
2016 HD Road Glide
Has thanked: 1 time
Been thanked: 14 times

Re: Front Cylinder Head Gasket Change.`

#7

Post by foundationapps »

I have STD heads. There appears to be a "fire ring" in the head, however, a non-metal ring head gasket was in place when I removed the head. Perhaps someone did a head gasket replacement that wasn't the engine builder. That was done in the 70s as far as I can determine (the original build by Volkswagon Bob).

I've been fitting an RSES electric starter to the 4-speed tranny, i'll update that on another posting I've been doing on the RSES. It's pretty amazing.

If anyone reading this can help out on a custom pipe builder..... I have a KraftTech frame, got a special deal on a wide tire frame setup. The frame had a 3-4 or 1" offset to the left for the engine and transmission so no spacers are used to push the drive train to the left. BUT, the new Paughco pipes I got won't fit that setup because the engine is 1" or so further to the left.

Who is a good custom pipe builder? I know they have to be around.

Respectfully
talldrifter
Member
Posts: 67
Joined: Tue Dec 21, 2010 6:48 am
Bikes: Aftermarket Panhead in Shovel frame, 1978 XLCR Sporty in disguise
Location: Tennessee
Been thanked: 3 times

Re: Front Cylinder Head Gasket Change.`

#8

Post by talldrifter »

The reply from Andygears was a little more direct than I would have written, but to the point and correct. You don't need to use James Gaskets "Fire ring" head gaskets, in my opinion it was not one of their better ideas. I also have STD heads mounted on S&S cylinders, and since my cylinders are 3 5/8 " the blue gaskets that I have found won't fit so I use S&S head gaskets, no metal ring and they work fine. You do need to do the proper maintenance and check those cylinder head bolts and cylinder base nuts with a torque wrench, or you can ignore them and tear the engine down to fix it. I have a set of those Fire Ring gaskets here, bought by an Indy with my money back in 1999, I will never use them, not sure why they are still here actually. That is about as plain spoken as I get, your engine so do what makes you happy.
Andygears
Senior Member
Posts: 1396
Joined: Tue Feb 05, 2013 12:25 am
Bikes: 1950 panhead, 1999 FLHTCI, 1987 FLHTC custom
Location: Daytona Beach
Has thanked: 438 times
Been thanked: 648 times

Re: Front Cylinder Head Gasket Change.`

#9

Post by Andygears »

I reread my post and I apologize if I was a bit harsh. I know it sucks when things break and you end up second guessing what could have been done avoid it.

I was not very understanding. Sorry.

Andygears
talldrifter
Member
Posts: 67
Joined: Tue Dec 21, 2010 6:48 am
Bikes: Aftermarket Panhead in Shovel frame, 1978 XLCR Sporty in disguise
Location: Tennessee
Been thanked: 3 times

Re: Front Cylinder Head Gasket Change.`

#10

Post by talldrifter »

foundationapps
I seem to be in a a bad mood, not sure why, except a trip to the ER for heart on Halloween then one of my house dogs died on 11/15 and I came down with the flue on 11/16 which morphed into some chest cold thing, trapped in the house. I don't have an ax to grind, just think those gaskets are not a good idea, then I got carried away, relieving pent up stress. Not your fault and should not take it out on you. I'll try to behave better in the future.
That RSES sounds like a good modification, I may do that in the future.
foundationapps
Member
Posts: 364
Joined: Tue Sep 01, 2015 9:26 pm
Bikes: 1948 Panhead
1985 FLHTC
2020 Electra Glide Standard
2016 HD Road Glide
Has thanked: 1 time
Been thanked: 14 times

Re: Front Cylinder Head Gasket Change.`

#11

Post by foundationapps »

Talldrifter,

Think nothing of it, sorry for the slow response, been doing fine work on the Panhead this weekend. Locked myself in the basement with paint fumes and the fine smell of engine oil.

Very sorry to hear about the loss of one of your dogs. We have two OLD dogs here, the Australian Shepard runs combat patrols around the yard all day long. Unstoppable. The Jack Russell just demands attention. Panhead engines on the floor make her act weird. :)

Relieving pent up stress is much needed. I do understand, we need an ear now and then.

Respectfully
Trig

Andygears,

Also, I understand, no worries on the response. I do appreciate the importance of brevity and someone asking the obvious without any sugar coating. My beat up brain appreciates that manner of speech, really! I learn tons of stuff from everyone here. Couldn't have done much to this machine without the fine guidance of the knowlegable on this site. Heck, I can't even spell right.
Post Reply

Return to “Cylinderheads”