It's a 1999 Heritage Softail Classic with 53,000 miles. The bike does not burn oil but the rear cylinder is leaking oil through the cylinder base gasket. My question is should I just pull the cylinder and leave the piston on the connecting rod or should I remove the wrist pin clip, tap the wrist pin out some and leave the piston in the cylinder then replace the base gasket, as to keep the piston rings in place?
I just pull the cylinder off.
So I can just pull the cylinder off, replace the gasket and put it back together. No need to hone the cylinders?
The cylinder can be placed back on to the piston. Just check ring spacing as you would on a new installation.
Thanks for the Replies. You have just saved me a lot of work. Thanks again to both of you.
I think I will just remove the cylinders. I don't think relaxing the rings will do anything negative. I was just worried about the seating of the rings. One more question. What is the torque for tightening the base bolts (nuts) and head bolts?
Usually the cylinder base and/or the engine case surfaces are not flat when a rear base gasket on a Evo leaks. Might want to consider this-https://www.haydensm6.com/tof_single.htm
Is there an easy way to check flatness of the engine case?
You might try using a precision straight edge and very thin feeler gauges. Ideally a dial indicator mounted and passed across the case service would tell.
Ok, so what would be the tolerance? .001, or less? .0001?
Unless I were planning on tearing it completely down if necessary to have the case machined and rebuild the motor, I would just put a new gasket on it and ride. The previous one lasted 22 years.
Usually, the Evo will get a pucker around the studs.
Pull the studs and choose your weapon to flatten it all out.
Install better grade stud.
Don't get any shavings dwn inside of course.
Or take the case halves to the proper machine shop.
choices.
The stock gaskets were crap,replace then with cometic gaskets and go.
In the past I have replaced leaking stock with James base gaskets. Last one I did was with Cometic. Good time to go with a thinner head gaskets usually too
If ya have Vergin heads, it's a great time to rip at least 0.50 off them.
Quote from: 4DogsanaHog on November 03, 2021, 05:37:09 AM
It's a 1999 Heritage Softail Classic with 53,000 miles. The bike does not burn oil but the rear cylinder is leaking oil through the cylinder base gasket. My question is should I just pull the cylinder and leave the piston on the connecting rod or should I remove the wrist pin clip, tap the wrist pin out some and leave the piston in the cylinder then replace the base gasket, as to keep the piston rings in place?
You should read this post about base gasket leak and cure.
https://harleytechtalk.com/htt/index.php/topic,115559.0/all.html (https://harleytechtalk.com/htt/index.php/topic,115559.0/all.html)
Check for a possible stud pulling out. If everything checks OK, get some "Pig Tails" and install, with a fresh metal COMETIC base gasket. :up:
John
for what it's worth...I did the pigtails, metal gaskets, and had the cylinder bases 'surfaced' in early 2020 and after only 6k miles have no leaks at all..... It doesn't hurt to try all the remedies.
(also new studs and head 'nuts' bored the cylinders and bumped compression a bit, but that's neither here nor there)
Evo, (and T/C for that matter) did not come from HD with any machining done to the cylinder base.
"As cast" surface only.
We mount the cylinder in a fixture, with the ID running on true C/L, and then skim machine the cylinder base.
The base is then totally perpendicular to the bore C/L.
Call California Phil, a vendor on their site.
Quote from: thumper 823 on November 03, 2021, 11:47:43 AM
If ya have Vergin heads, it's a great time to rip at least 0.50 off them.
Half an inch off the heads?
Good luck with that.
I think most people can read beyond a typo?
To clarify 0.050
There, feel better?
Just curious. How much more power would you get by shaving .050 off the heads? Or what difference would shaving .050 off the heads? I have a set of like new very low mileage heads for my Evo. They are shaved down to .060. Maybe I should install these?
Check your clearances as per SOP.
And install them!
You will have upped your CR a point or two.
Slippery slope and it is the way to travel.
When I attended the factory police mechanics classes in 1992 they were already on the 14th version of the base gasket since 1984.
I have James Foam-met base gaskets in my otherwise stock '92. Bone dry at the cylinder bases. These new type of gaskets appear to be pretty forgiving of surface to surface imperfections.
According to my machine shop guy, who's worked on a ton of San Jose police bikes, police EVOs came from the factory with .050 off the heads. So I say go for it.
-JW
Some of the heads can have 0.075 ripped off from the factory as they are not very QC in that area..
Once we start dwn the road here...we could say CCing them might be a good idea...
BUT-
It is all too EZ to spin a web for someone that is not up to speed on this stuff.
If you up the CR, you will prolly have to go up a fudge on the carb depending on the pipes etc .
Next, the nodular iron jugs need no base gasket.
This is especially helpful for getting for squish setting correct, as cometic will custom make you most any thickness you want.
Slippery slope.
Cleaning the cylinders and heads to reassemble the engine, I noticed rubber O-rings on the 2 protruding oil passage pipes. Well I didn't notice them while buffing the top surface of one of the cylinders in preparation to reassemble the head to cylinder and tore them up. Are these O-rings really necessary? Seems to me the head gasket would not allow oil to leak between the head and cylinder. The Harley dealer closest to me, 100 miles, has only one of these O-rings in stock. Are these O-rings really necessary? Can't I just leave them out?
I wouldn't leave them out.
Quote from: 4DogsanaHog on November 07, 2021, 06:40:17 AMCleaning the cylinders and heads to reassemble the engine, I noticed rubber O-rings on the 2 protruding oil passage pipes. Well I didn't notice them while buffing the top surface of one of the cylinders in preparation to reassemble the head to cylinder and tore them up. Are these O-rings really necessary? Seems to me the head gasket would not allow oil to leak between the head and cylinder. The Harley dealer closest to me, 100 miles, has only one of these O-rings in stock. Are these O-rings really necessary? Can't I just leave them out?
I believe Cometic and newer oem gaskets do not require the oring on top of cylinder. They are usually embossed around the dowel area. They fit snug up against dowel and there would be no room for oring...jimmy
I believe he's using OEM gaskets.
Yes, I'm using OEM gaskets. Just got some new O-rings and will put them in.
New OEM gaskets wont use the oring on the dowels. Put the gasket on the dowel, if there is no room for the oring, dont use one
if the plugs are running clean-not burning oil and your not up to a complete top end rebuild while apart, leave the piston in the cylinder. If you remove the piston it does need to be re-honed and new rings. Pull the front one also. Replace the cylinder studs and use the appropriate lock-tite, torque tool-CYLINDER STUD REMOVAL TOOL FOR EVOLUTION & TWIN CAM-, use metal base gasket sets for the cylinder base(cometic has served me well).
Quote from: astropi on March 01, 2022, 03:31:32 PMIf you remove the piston it does need to be re-honed and new rings.
This is incorrect. Many here including me have performed the operation of removing a cylinder and placing it back on the same rings without honing the cylinder with zero ill effects.
Do you think that HD replaced all of the piston rings and honed the cylinders of all of the warranty Evo's that leaked base gaskets in the early 90's? You do more damage to the cylinder honing it by hand unless you have cylinder torque plates and a hone with a micrometer adjustable head.
Quote from: astropi on March 01, 2022, 03:31:32 PMIf you remove the piston it does need to be re-honed and new rings.
Pulled heaps and re-installed Evo & Twin Cam and no issues at all.
Internet myth this re-honing and new rings.
Never heard about it until I read it on the internet and can't for the life of me work out why I never had any problems :hyst:
Quote from: astropi on March 01, 2022, 03:31:32 PMif the plugs are running clean-not burning oil and your not up to a complete top end rebuild while apart, leave the piston in the cylinder. If you remove the piston it does need to be re-honed and new rings. Pull the front one also. Replace the cylinder studs and use the appropriate lock-tite, torque tool-CYLINDER STUD REMOVAL TOOL FOR EVOLUTION & TWIN CAM-, use metal base gasket sets for the cylinder base(cometic has served me well).
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Rear base leaking is common , I found that waiting for the motor to warm up helped a lot .
If you pull the cylinder you should at the very least hone and new rings . The rings will not seat properly . You have to warm up an Evo before you ride . Not warming up the bike is the main cause of base gasket leaks . This is from over 40 years of wrenching on bikes . If you do a job, don't do it half assed or it will bite you in yours .
Quote from: Ohio HD on March 01, 2022, 03:43:28 PMQuote from: astropi on March 01, 2022, 03:31:32 PMIf you remove the piston it does need to be re-honed and new rings.
This is incorrect. Many here including me have performed the operation of removing a cylinder and placing it back on the same rings without honing the cylinder with zero ill effects.
Do you think that HD replaced all of the piston rings and honed the cylinders of all of the warranty Evo's that leaked base gaskets in the early 90's? You do more damage to the cylinder honing it by hand unless you have cylinder torque plates and a hone with a micrometer adjustable head.
Quote from: Scotty on March 01, 2022, 03:46:12 PMQuote from: astropi on March 01, 2022, 03:31:32 PMIf you remove the piston it does need to be re-honed and new rings.
Pulled heaps and re-installed Evo & Twin Cam and no issues at all.
Internet myth this re-honing and new rings.
Never heard about it until I read it on the internet and can't for the life of me work out why I never had any problems :hyst:
Quote from: Ironheadmike on March 13, 2022, 08:55:14 AMIf you pull the cylinder you should at the very least hone and new rings . The rings will not seat properly . You have to warm up an Evo before you ride . Not warming up the bike is the main cause of base gasket leaks . This is from over 40 years of wrenching on bikes . If you do a job, don't do it half assed or it will bite you in yours .
Or not
Yes you should use boring rings to hone . I never hand hone . Just because people don't hone doesn't make it right . Why do thing half asses . Harley have always done the cheapest and easiest thing possible . I personally have seen them reuse gaskets and seals . Sorry I don't gamble on anything .
It's an Internet myth and an old wives tale to replace rings when pulling them from a cylinder.
Rings do in fact tend to move around the bore when the motor is running. So pulling them out and reinserting them changes absolutely nothing.
Piston Rings and Grooves by Wiseco (http://blog.wiseco.com/ring-grooves)
I didn't see anyone mention leave piston in cylinder and remove wrist pin.
I guess that is a question of how many hands you have to do this. It is a real PITA to hold the cylinder, get those piston pin clips out, and then get the pins out of the pistons. But in my opinion, it's all moot. There is no need at all or any advantage to leave the pistons in the cylinders. Unless you don't have a ring compressor?
-JW
Quote from: Ironheadmike on March 13, 2022, 08:55:14 AMIf you do a job, don't do it half assed or it will bite you in yours .
40+ years as well and has not bitten me yet................
Even without a ring compressor you can use a simple popsicle stick and your finger tips on each individual ring as you slide the barrel on. You can stagger the ring gaps easily too. A dowel of sorts under the piston allows you to slip the piston into the cylinder at a height that gives you plenty of room to work and see what you are doing. It has worked so well for me that I have left my ring compressor in the drawer. I now keep a few popsicle sticks in my tool box too.
Well I was kind of being a dick about the ring compressor remark, but now that you brought it up...
A popsicle stick? I'm trying to picture that one there kd. You have to hold the cylinder with one hand, so that leaves you with only one more to squeeze the rings into the bore. Hmm. Am I missing something? Please make a video of that next time you do it, love to see/learn how this is done.
:SM:
OK... so do you cock the cylinder, start one end of the ring, and walk the popsicle stick around the piston until the other end is in?
:scratch:
I use one of those Rowe band type ring compressors, works perfectly.
-JW
FWIW I am totally on board with you being a dick. :hyst: NO no just kidding. I'm on side with the pull the barrel off and slip it back on method. :wink: Wrist pin clips can disappear and in that situation and you'll neve know if it made it past that rag you have stuffed in your cases around the rod, stuck in the tread of your boot, under the bench or who knows where. :emoGroan:
Using the popsicle stick is pretty much as you envision it with the stick on the rings for reassembly.
Someone on here mentioned it years ago so I tried it. Dowels crossway on the piston skirt front and rear of the rod stabilizes the piston. Slide the barrel on up to the piston and feed it in to the first ring. You no longer really have to hold it. Remember that the spigot hole does not have a sharp edge in the bore so the ring will feed in. One hand starts the ring in and the other gently coaxes the ring up to each end at the ring gap with the popsicle stick on the flat around the spigot until it slips inside. (it's helpful to have at least normal fingernails but the spigot depth and piston height gives plenty of finger room to start the ring) The side of your hands by your thumbs and installed ring friction just naturally stop the barrel from dropping hard to the next ring. Once there is a ring in the bore the friction is your friend. Rinse and repeat making sure the ring gaps are where you want them on each set before feeding them in. I found it so easy peasy that I am serious that the ring compressor is seeming to be more work. Now, I can't say it would be a cake walk on a shovel or any other base mounted cylinder. It sure works well with full length studs and the piston supported above the case deck.