My '86 Tour Glide is now at 65K original miles. The gasket set on it now is Cometic and were on it when I bought this 5 years ago with 37K. I added an EV27 and new lifters at 43K. Other than developing base gasket leaks and now head gasket issues I have had thousands of miles of trouble free riding with only carb issues and intake seal replacement. I rebuilt the stock carb and finally have it working perfect.

My last ride November 15th, 2013 I noticed hot vapor on my left leg when first starting. In seconds it stopped. It must have sealed as it warmed up, before rolling out. It didn't give me any running issues other than weeping some blow by oil on the rear cylinder head gasket. I had also noticed a minor oil weep on the front cylinder head gasket, it's been that way for a long time without any blow by.

I did a whole lot of reading on this issue and found this thread Blown Head Gasket from 2011 that had a lot of good info for my repairs.

I haven't done a compression test, or a leak down but it had great performance and high MPG all last summer. Then the mileage dropped off at the end of riding season and I knew something had changed.

I have not started working on this because I am concerned about possible issues with the cylinder studs. I now know if they are to spec and show no signs of issues to not mess with them. But with the gasket leaks I think there's an underlying reason. I'm going to plan on replacing all of the corroded head bolts.

Does my 86 have the flanged studs? Would the flange be on top if stock?

Purchasing the studs will wait until tear down and inspection. So I'm planning for a gasket set, wrist pin clips and new head bolts to be the only real parts involved.

I suspect the cylinders, rings and pistons are also a wait and see matter. I'm thinking I should at least take the cylinders in for a hone and new rings? I'm hoping to stay with original pistons.

When working on the intake last spring I noted blackened, baked on oil on the back of both valves. Doesn't that mean it's time to do something about the guides too? I don't suspect the seats are bad but should I have them installed while it's torn down? Any advice on this condition or other head concerns would be helpful. What type of machine shop will be able to check them and do what's needed?



Anything else I should know about the '86 EVO.

 

When I noticed my base gaskets leaking I called Scott at Hillside to get his recommendations.

About studs he told me that in 20 years he has only replace about 4 sets and that was because the customer wanted him to not because he thought they needed to.

Looks like a valve job is in order!!!!!!!!!!

 

I would say it's the valve guide seals, not the actual valve guides causing the buildup on the back of the valves. That is probably what you meant, anyway.

 

johnny, it is burning oil as can be seen in the deposits on the valve stem and guides. As for the hot air on your leg at startup, sounds like the head gasket was leaking. Anyway, the oil problem is either in the heads at the valve guide seal or the rings. To check guides and replace the stem seals would normally require removing the heads which it looks like you have already done. It only takes a set of rings and a couple base gaskets to knock out both potential sources of the oil problem. At these miles you should go ahead and get the valves and rings back to good working order for many more years of trouble free riding. I would not try to put a band-aid on the problem. If it were me, I would check the guides, lap or grind the valves and seats and replace the valve stem seals, check the cylinder bore, and if good, bust the glaze and replace the rings. Then when I put it back together I would use James Silicone Bead Base Gaskets which are thicker than the stock paper but would never ever leak at the base again. As for the studs, I have never replaced the studs in an EVO rebuild. I have on Twin Cams with High Comp pistons but never on an EVO even with High Comp pistons

 

Replace with later style studs and have block threads checked ,deck motor and have barrel ends trued to start with.

 

Many thanks already for the comments and info.

I have not tore it down yet. The intake valve photos came from the manifold seal replacement and carb rebuild last spring. Plugs don't show any signs of oil but I have noted a bit more white smoke than usual at start up while warming.

Valve guide SEAL. That's good to know I was thinking the entire guide had to be replaced. I'll bet those seals are in the gasket set. I have seen the seats sold separate and I know that it takes a special device to seat the seats. I wonder if the dealer does that type of piece work?

 

Smoke on start up = seals, get the guides checked while you are in there....they last for ages but Kees had to replace his at 100,000 miles.

If the base gaskets fall apart the head gaskets can lose tension and then you get leaks.

 

White smoke at startup can also just be moisture in your mufflers. Also rich jetting can cause buildup on the valves. If you are convinced you need valve guide seals, there are ways to do that without removing the heads. I have used air thru the spark plug hole to hole a valve up while servicing the valve guide seals. Basically I knock the center out of a spark plug and TIG weld on a quick disconnect for my airhose. It is risky as when you apply air the piston pushes to the bottom and if you loose air the valve may slide down in. I have heard of people bringing their pistons to Top Dead Center then pushing rope into the spark plug hole as a way to keep a valve from falling in. Either way, once you have the valve held up, you can then use a valve spring compressor tool to remove the spring with the head on the bike. All you remove is the gas tank and the rocker box top, the rocker arm asm and the valve spring keepers.

Seals come in the top end kit and there is also a short straw piece to cover the top of the valve, keeper grooves. Be sure you place the cover over the top of the valve before sliding over your new seal.

 

Get those heads checked by a reputable Bike machine shop do'nt use a automotive machine shop that has no experience with H-D's ( i have been bitten by this to the tune of $800) they are completely different animals . With the amount of miles be prepared to bore and fit new pistons not saying it Will need them but I started my eng. build budget at $1000 this year and I am now at $1900 figured while its apart to do a lot more . Have the heads and cyl. decks checked , also be sure your oil returns are clear on the block i have seen guys leave broken pieces of base gasket wedged in the holes .

 

When heads are checked out have machinist pay close attention to exhaust guides ,as they can come loose.