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1985 FLHTC Top end rebuild

BOBFLHTC

BOBFLHTC

Active Member
My bike has 82500 miles on it. I was thinking of sending the motor back to Harley for a Reman but it would clean me out so I decided to rebuild the top end myself. I figured if I botch it then I can go back to the Reman option slightly poorer but wiser. I hate to take it apart during the summer but its making a good deal of noise from what appears to be the valve train. I have disassembled it down to the engine and I was removing the Rocker covers this evening. The front came off pretty easy. The rear lacks clearance between the cover bolts and the frame. I changed the Rocker gaskets about 10 years ago and there seemed to be clearance then. I went back and read the manual which clearly states to lower the engine by taking the bolts out of the front motor mount and stabalizer. The last time I changed Rocker gaskets I had a broken motor mount that I didn't know about and which a shop found some time later so I guess thats why I had clearance that first time 10 years ago. Its also giving me an opportunity to clean places that are hard to get to and straighten out the wiring harness. The white lining in my gas tank are starting to flake and clog the Petcock strainer so I can deal with that too. Questions to follow - Bob
 
A good valve job, and insure the bores are round/straight, along with a set of lifters,(Moco bulletin to inspect/replace at 25,000) cam bearing.
Check the male rod at the crank pin 5 o'clock postion for up/down, void of oil.:s
Scott
 
If you remove the jugs make sure you have some one with torque plates do the finish work on them:s
 
The Base gasket is leaking so I'll be sorry if I don't attend to it. I'm going to order OEM parts from BikeBandit. They seem to have some good prices on the OEM. I found a citrus spray cleaner called Dep at Autozone to clean up the parts which is working pretty well and bagging and labeling eveything in zip locks. The motor mount was replaced about 25000 ago but the bolt was rusty so I am replacing it. Its all the little stuff you do because it's your bike that someone else might not attend to. Once I have the cyclinders and heads off I need to call around to see who is available to work on them. Worse case I could get more help than that since I have the bike on my trailer. Thanks for the feedback - Bob
 
Bob; It's recommended that the cylinder studs be replaced any time the heads are removed. I reused mine ('92) with no problem, but they should be re torqued. I would also use Cometic base gaskets. I used stock, and have small leaks.
 
The stock base gaskets can be a wee bit stuborn and want to stay where they are so allow a fair bit of time for clean removal

Brian
 
Cometic gasket set.
Insure round/straight bores.
Lifters.
Cam bearing.
Wood 6, or Andrews 27 cam.
Good valve job, and perhaps a 1.900" intake valve replacement.
Re-surface heads, .070".
46 pilot jet/180 main for starters.
Adjust timing accordingly.
Huge increase in power, super-smooth, and fuel economy WILL be up.:s
Scott
 
Well I had the heads and cylinders off and brought them to an independent for evaluation. Even before he took a close look it became apparent it was going to blow my budget so I decided to try honing them myself and settle for a valve lap rather than a proper valve job. The next day I went looking for a flex hone and after 2 stops decided to ask the Harley dealer where I was picking up some rings anyway where I might find one. The dealer, Mills located in Burlington, NJ is going out of business the end of the month. The parts guy went to the back to ask the machinist about it. He came out and said he could hone the cylinders and take a little off the bottoms for a 30 minuet labor charge if that’s all I wanted which sounded pretty good to me so I ran home and grabbed an empty Yuengling box (my personal favorite) and put the cylinders and pistons in it. I asked him to check everything out and put the rings on for me too. As he carried the box to his work station I could hear a chorus of approval go up from his co-workers only to turn to disappointment when it turned out they were just motorcycle parts after all.
Several days later when I went to pick up the pistons and cylinders I decided to throw the heads in yet another empty Yuengling box since he indicated he had the time to look at them. He was surprised when all the parts looked so good after 25 years and 82500 miles, a testimony to how well these bikes are made and the value of changing oil/filter every 3K ? He made a comment about how much beer I consumed too. I heard the same groans as he headed back with the heads in the new Yuengling box.
Yesterday after work when I picked up the heads I figured I needed to make it right by dropping off a case of cold Yuengling after the ribbing he took. He did a great job and everything looks like new. It was just over a 2 hour labor charge for everything. He honed the wrist pins to move more freely and supplied new clips for the pistons. He ground the valves and seats and put in new seals, cleaned up the mounting surfaces and put it all back together with a new paint job and gave me some pointers about putting it back together. I’m sure I am leaving something out. I understand he is going to start working out of his home so I wish him well and will keep track of his number.
I ordered a set of SE cylinder studs and a set of stud screws to go with them. I have seen some discussion about replacing the studs but in my case while not as apparent the screws were the more worn. I flushed them with parts cleaner and ran a brush in them and a lot of metal came out. I also ordered a Hayden Oil fix kit to address the base gasket leak issue for EVO’s. I pulled the Tappets to replace them but they looked as good as the new ones so I put them back with new gaskets. So everything above the Tappets will either be new or refurbished. I could do more but I’m anxious to ride and I suffer from a bad case of Defundsalow. I’m curious to see how it runs as is too. I also cleaned up some wiring under the tank, flushed the fuel tank and replaced a cracked motor mount while I was at it. I’m thinking of swapping 2 of the Allen screws on the rear cover for hex head on the Primary side so they can be tightened without dropping the motor. I’m also thinking of turning it over by hand without the plugs to make sure I don’t hear any really bad noises before I try starting it.
I’ve learned a lot and feel more comfortable trouble shooting or making performance changes in the future and there is that whole personal satisfaction thing going on so far too. Its long winded but I thought you might enjoy the story - Bob
 
If i was you id keep good friends with the mech that did all the work sounds like he cares about what he is doing
remember to go through the new motor brake in procedure especially the ring seating procedure
And enjoy your newly rebuilt motor

Brian
 
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