Board index Flathead Power-Technical Questions, Answers, and Suggestions Evo's Thru 99 evo head gaskets

evo head gaskets

Moderators: Curt!, Pa

Post Wed Oct 03, 2007 9:10 pm

Posts: 7
Hey Guys,
I rebuilt the top end of my 87 dresser about 4 years ago and used James Gaskets. I put about 31000 miles on it since. I just blew a head gasket ( composite with metal squash ring ). Wanted to know if there is a better head gasket or better material to use for the evo. I torqued to 65 ft/lbs when I put the motor back together and never torqued them again, since the head bolts are under the valve covers. Any info would be greatly appreciated!!!

Post Tue Nov 06, 2007 9:14 am

Posts: 2683
Location: Los Angeles, CA
Most of the time head gasket failure in Evo's can be tracked down to a slipped cylinder sleeve.

Post Tue Nov 06, 2007 9:33 pm

Posts: 7
Hey Chris, thanks for your reply. When I take the evo apart I will look for slip. Any other advice before I rebuild the upper end this winter?
Thanks,
Tony

Post Mon Nov 19, 2007 7:54 am

Posts: 202
Location: Middle England UK
Always re-torque.
You can get tool for removing covers in frame

http://www.motionpro.com/motorcycle/too ... ver_wrench
Also from CCI Dealer.

Post Mon Nov 19, 2007 4:53 pm

Posts: 122
Location: Mpls. area
I thought evo head bolt tourque was 45lbs plus 90 degrees ? Mike

Post Wed Dec 19, 2007 10:24 am

Posts: 903
Location: Hill City, Ks. USA

It's been a while since I've built an evo motor, but I remember HD's recommendation that you NOT re-torque the head/cylinder nuts. I've never had a problem with the James teflon head gaskets, but there is a fire-ring (some call Blow Pruf) gasket available. There is a GB 3 piece Stainless steel/rubber sandwiched head gasket that is supposed to be really good, but I've never tried them. Riviera has a copper head gasket that they recommend.
Curt!

Post Thu Dec 20, 2007 10:10 pm

Posts: 7
Curt,
Thanks for your help on the head gaskets. I will start on the rebuild sometime in January. I'm interested in finding them copper gaskets and giving them a try. If not, I will use the James gaskets again.
Thanks,
Tony

Post Thu Dec 20, 2007 11:47 pm

Posts: 2683
Location: Los Angeles, CA
Remember that is inch pounds and not foot pounds.

Post Thu Jan 03, 2008 11:23 am

Posts: 903
Location: Hill City, Ks. USA

DocTony
The Riviera gaskets are available from any V-Twin dealer. If you don't have one close send me an e-mail and I'll mail a set out to you.
Curt!

Post Mon Feb 25, 2008 12:51 am

Posts: 1538
Chris- evo sleeves are pressed-in with a patened 'spiny-lok' design, that just doesn't let go.
Most Evo head gasket failures I have seen are related to not allowing the motor to warm up thoroughly to expand the cylinders for the best seal, before ya go WFO down the road..
This is also a reason for lots of base gaskets starting to leak..
"Remember that is inch pounds and not foot pounds" I don't think so..

limey-dave- you can easily make the tool, just cut off a 1/4" of the allen wrench & use a hand wrench on the stub..

Post Wed Feb 27, 2008 11:12 am

Posts: 2683
Location: Los Angeles, CA
[quote="sleeper"]Chris- evo sleeves are pressed-in with a patened 'spiny-lok' design, that just doesn't let go.


Most things are designed to function properly. That doesn't mean they are fool proof.
Both cylinders on my 1995 Ultra Classic had to be replaced when the sleeves slipped. The slippage was discovered the second time the headgaskets had to be replaced. :(

Post Sat Mar 01, 2008 11:30 pm

Posts: 1538
chris- you mean that BOTH cylinders did this at the same time, twice ??

I think the nut behind the handle bars may need adjusted... :lol:

Post Sun Mar 02, 2008 12:41 am

Posts: 2683
Location: Los Angeles, CA
sleeper wrote:
chris- you mean that BOTH cylinders did this at the same time, twice ??

I think the nut behind the handle bars may need adjusted... :lol:



My headgaskets were replaced and blew again a few thousand miles later. It was then that the slipped liners were noticed. Too many hard miles in the Great American Desert.

Post Wed Mar 05, 2008 11:21 pm

Posts: 1538
Chris- both blew, & both blew again at the same times ??? What are the odds of that ??
Maybe the wrench that did the work just tightened your nuts

Post Thu Mar 06, 2008 10:17 am

Posts: 2683
Location: Los Angeles, CA
sleeper wrote:
Chris- both blew, & both blew again at the same times ??? What are the odds of that ??
Maybe the wrench that did the work just tightened your nuts



No, Not at the same time. The first one blew as I was entering Milwaukee. I limped into the dealer and had it replaced. 20 miles after leaving the dealership the second one blew.

Post Sat Apr 26, 2008 11:16 pm

Posts: 7
Hey Guys,
Just started the upper end rebuild in April. Had a few setbacks....heads rebuilt...divorce...new pistons, rings. Anyone know anything about the Hayden oil fix kit for the evo motor? Comes with an oil jet that slips into the oil passage hole between the case and the cylinders and base gaskets. Any Good or Bad? Also went back to HD Speed Shop and was told to torque heads down with 440 inch pounds. This works out to be 40 Foot lbs but it seems a little light any specs. Thanks again for all your help.

Post Mon Apr 28, 2008 10:48 pm

Posts: 1538
DocTony-

The Hayden oil-fix set-up was invented cause some folks don't let their evos warm up before running them hard. This is critical to allow the jugs to expand & make the best seal before running hard. If not "base gasket(s)" can & will start leaking.
The Hayden fix does work well, & so does allowing the motor to warm up first.. U decide..

As far as torquing the heads. That's about rite.
Must go up in sequential increments tho..(that IS important)..
1st round 7 ft lbs
2nd round 15 ft lbs
3rd round= make a quarter or 90* turn to all, which equals about 40-45 ft lbs. That's it.
If all was clean & torqued evenly, then after warm-up, go enjoy yer ride...
No re-torque is necessary...

Post Tue Oct 14, 2008 11:15 pm

Posts: 1538
Have been trying out "Cometic" MLS head gaskets .030 thick... So far so good, bout 2k on them now...

Post Sun Nov 29, 2009 10:16 pm

Posts: 113
Location: Plattsburgh, NY, USA

Harley sez to not retorque head gaskets?? Why - I don't know Here's what I do
Put Napa gasket sealer [blue stuff in the tin can with a brush] on cylinder stud threads,very lightly oil the bottom of the headbolts where they contact the head. torque the heads in a cross X pattern 5 ft lbs at a time until 20 ft lbs is hit. Continue torquing the heads in 2 ft lb increments [x pattern]until 42 ft lbs is attained. Assemble the intake/carb and start the bike with a remote gas bottle. Direct 2 household fans [on high] at 45 degree angles to the engine. Run the engine until it reaches operating temp. Shut the engine down but leave the fans on until the engine is dead cold. Retorque the heads using offset/dogbone wrenches starting at 30 ft lbs in 2ft lb increments [X pattern] until you hit 42 ft lbs. [You have to use a math table that come with the dogbones so you can correctly set you torque wrench, Don't Over torque!!] Assemble the bike and ride!!
A few things noted:
Install all head and basegaskets dry.
The Napa gasket sealer acts as a lube for torquing and sealer. If you heavily oil the studs the oil will run down the studs & contaminate the base gasket before you can properly torque the head.
HD sez to torque the heads front- back. Don't do it!! Try this test. Put a dial indicator on the head as you torque . It will lift the head .030-.045. on the untorqued side. On HD factory videos it shows the factory torquing the headbolts all at once with a 4 socket pneumatic special tool.
I don't know where the hell they got the front/back torque procedure. Don't do it!!
You must retorque the head after start up!! HD Evo engines grow .080-.090 when they reach full operating temperature. When you retorque you always find 1 or 2 loose headbolts!!
DO NOT be lazy and try to torque the heads in more than 2 ft lb increments from 20 ft lbs to 42 ft lbs. You run the danger of snapping a stud!!
This procedure takes a little more time but its worth it in the long run.

Post Mon Nov 30, 2009 9:14 am
panic

440 ÷ 12 = 40?

If you've seen a see-through of the Spiny-Loc cylinders you'll understand how "slipped" requires shearing off a few dozen points of interference in which the liner's OD is keyed into the aluminum casting. I doubt it could be done with a press.
3 explanations:
1. the mechanics are liars ("what funny story should we tell them today?")
2. engine originally built with defective (and probably recalled) cylinders - never heard of it, but possible.
3. if you're not the original owner - the cylinders were replaced with press-in liner types (no one but H-D uses S-L).

In my limited experience, the single most common cause was a slipped base gasket caused by running the engine hard when dead cold.

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