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Discussion Starter #1
I've got a 1991 FLT with around 76,000 miles on it. Yesterday the top end sounded like something came loose but it stopped fairly quickly once it warmed up and ran fine after that. Today I took a short ride at lunch and it started again, really loud, almost like some tin is scraping inside the primary but the noise is coming from the top end. Had a few sputters but otherwise ran fine for the most part except for the noise. Made it back to the current job's parking lot. Had a retired guy who comes in for a weekly lunch visit with his former co-workers, and who also builds some custom bikes on the side, I had him take a listen to it and he said it sounded like a valve or possibly a rocker or lifter.

Does this sound familiar to anyone? It's a 40 mile ride back to the house and it ran fine this morning all the way in, and ran fine at lunch until I was on the way back. Started acting up when I got on the throttle a bit merging onto a street, but didn't get close to the redline.

Bike is stock as far as I know, I believe I'm the second owner of it and have had it for several years now. It did get a bit hot during one of the recent H-D events when I was stuck in traffic a few years ago (the Elton John year).

I'm thinking of just taking my chance and try to nurse it home since the noise did stop yesterday, unless someone here convinces me otherwise. I don't think it will fit in my utility trailer which is barely big enough for the '95 Buell S2. Not sure how the wheelbase compares between the Buell and the FLT, but it seems like the FLT is a foot longer which would have the rear tire hanging off the back of the trailer. Guess I'll start shopping for a little bit longer trailer as well, but for now I need to get the bagger home and as long as it won't totally lunch the engine I'm hoping I can ride it back.

Close to the season end for the most part, and I had planned to do some work on the bike anyway this winter if I found a new job (current one scheduled to end in a few weeks).

Comments? Let me know if you need any better explanations, and I know diagnosing a bike sound over the web via text doesn't work too well, but hopefully this "sounds" like something someone here has experiences before with these engines.

Thanks in advance for any suggestions or input.
 

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Could it be a lifter not pumping up?
 

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Discussion Starter #3
Not sure, hopefully could be something that simple. That would explain it getting better yesterday.
 

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It isn't hard to pull the valve covers and check your push rod to rocker clearance but give this post a little time to bring a few more thoughts to the table before tearing into it.
 

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You're getting off work and want to ride home aren't you?

Try holding a short piece of wood or something similar from your ear to the engine. It will transfer noise. One of the guys on this forum said he uses a 3/8 extension and puts his thumb between it and his ear. That sounded like a good idea. Pay close attention to the lifters and also to both sides of the rocker box cover. Maybe you can identify where the noise is coming from.
 

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If the lifters in your engine are original, you should replace them as soon as possible. A roller failure on a lifter can cause substantial damage to the engine.
 

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Discussion Starter #7
Got it home okay, sound varied a bit better and worse off and on. About a month ago it had a harsh rattely sound and in trying to track that down I found a cracked heat shield on the exhaust, removed it and the sound went away so I figured problem solved, now I'm thinking maybe not.

Running it here at home the sound is definitely seeming like it is coming from the rocker area. There is so much tin and chrome on this thing that once one part rattles it's like a whole sympthony/orchestra (sp?) Joins in as all the other bits kick in their own harmonics. But it does appear to be in the top end.

Ran fine on the way home apart from the noise so I'm hoping the guy at work might have been wrong about a burned valve or broken valve spring, or maybe that's going on as well.

In any case it is looking like I'll be pulling the rocker covers. Thanks for the input, I'll be sure to follow up with whatever I find out.
 

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Discussion Starter #8 (Edited)
Hello, finally found my way back to this thread, and finally started working on the bike again. Was off work for a few years and finding contract jobs to make ends meet, hopefully the current job will last long enough to get this bike back on the road. Anyway ....

This past weekend I was turning the engine over with the starter and could hear an occasional clack or whack like someone was inside the engine tapping something with a hammer. Almost like something lets loose or maybe sticks and snaps back into position or something (trying to describe sounds with words is iffy at best). Hard to tell where the noise was coming from.

So I pulled off the primary cover (and associated stuff that's in the way on a bagger) and all looks well in there. I went ahead and removed the primary chain slider/adjuster just to see if maybe the bracket or teflon shoe were cracked, but they look good.

I put a big socket on the mainshaft bolt so I could turn the engine over by hand and every few revolutions I would get either a soft or sometimes a firm whack from somewhere. I could not tell for certain where, once it sounded like from the front rocker area, then another time from down in the case, then again maybe towards the tranny region. Frustrating how sound travels in connected mechanical assemblies.

So I went ahead and removed the seat and tank and managed to get the top portion of the front rocker cover off. Turning it over by hand all appears to be functioning correctly. It got late and my wife came home so that's as far as I've gotten so far. I also have the pushrod tubes loose and collapsed and the rods appear to be straight.

If I do have a broken valvespring, can that be seen from above without removing the rockers? It's been a long time since I've had to dig into one of these engines (last one was a 1942 Knucklehead, and the Buells haven't needed any engine work yet). I've also managed to misplace my repair book somehow, argh.

Anything else that I should maybe check? Not having the book handy so I need to ask, is it possible to remove the pushrods and lift out the lifters without removing the engine heads?

I'm probably going to remove the rear rocker top cover this week/weekend and then connect the jumper cables up again and see if I can isolate where the noise is coming from.

Thanks for any direction or input, hopefully it won't be another three years before I get this issue sorted out and repaired.
 

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Yes, you can remove the pushrods without removing the heads. If the pushrods are one-piece stock pushrods, then you can either cut them with bolt cutters or remove the rockers. If they are adjustable pushrods, then you can hold up the pushrod tubes and use wrenches to collapse the rods and remove them.

If you are taking the top of the rocker boxes off anyway, then just remove the rockers and the pushrods will come out and then you can remove the lifter blocks and lifters and inspect them. If you have the stock pushrods, make sure you mark them as to where they go...they are not the same length. Find your manual. I'm thinking you have a bad lifter, but difficult to know for sure till you rip and tear it apart. Hope you find the problem in the near future.
 

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Discussion Starter #10 (Edited)
Thanks for the input. I did find my service/repair manual finally, hiding on a lower corner of a book shelf behind a box.

I need to shorten an allen wrench to get the rear rocker cover off, too close to the frame otherwise. I looked at the front valve springs as best as I could and they appear okay. Tonight I turned it over by hand again and every 2 to 8 revolutions there is a firm knock from somewhere. I guess it could be a lifter roller or something. Will have to investigate more over the next day or three.

edit: I might corner a neighbor to turn the engine over so I can listen closer and not have to crank it at the same time. Or I'll probably just start with pulling the lifters since that seems straight forward enough.
 

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If it's a lifter you will be able to spin the culprit pushrod easily when you hear the knock. Too much side play in the rocker shaft will give a knock also but it shouldn't be as loud as you say it is.

If you hear the knock at either the very top or the bottom of the stroke you might have a crank/rod/or wrist pin problem.

Good Luck Dude
 

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Discussion Starter #12
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If you hear the knock at either the very top or the bottom of the stroke you might have a crank/rod/or wrist pin problem.

Good Luck Dude
I sure hope that isn't the issue, might be down for the count if it is. If that is the case then I'll be hitting the local classifieds and barter sites for a donor engine.
 

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Discussion Starter #13
I just got home from work and got curious. For some reason I've never lifted up the pushrod covers, just pulled them down, so I went out and lifted them upward and lo and behold they are adjustable pushrods. Shake my timbers, that saves me a bit of hassle and also indicates something has been done before in this area of the bike. As long as the ends of these pushrods are in decent shape this saves me a few dollars.

So now I've got some work to do this weekend and see what else I can find out as I try and figure out where the noise is coming from.
 

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You can hold the pushrod covers up with clothespins or wire bent at both ends while you have someone turn the engine over. You can use both hands and touch all four pushrods at the same time and feel where the clunk is. Then you will know which rocker, head, or lifter block to take apart. I'm still of the opinion one of the rollers on a lifter went south.

Go slow and methodical.
 

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Discussion Starter #15 (Edited)
Shiznit, got a bad lifter, a very bad lifter, as in any needle bearings are probably powdered bad since the roller is extremely loose. So now I need to figure out how far I should go to rectify the situation.

I'm thinking:
1. New lifters (4)
2. New cam
3. Probably new pushrods ( 1 or all four?)
4. Gaskets as required (primary side, rocker cover gaskets/seals, cam side, probably oil pump, ....)
5. Cam bearing(s) that I've been reading about

I'm thinking I should remove the rear cylinder lifters and look at them. Then start working my way into the cam and oil pump stuff while watching for debris. I really hope I don't need to pull the engine and split the cases because then the can of worms will be opened and the whole mission creep will set in (restrained heavily by budget limitations) and who knows where it will end. I'm really hoping I can limit this to cam and lifters and gaskets and cam bearings.

Sheesh.


 

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Discussion Starter #16 (Edited)
If nobody minds too much I think I'm just going to keep posting to this thread as I work out the repairs and get the bike back on the road. This will also help me to sort things out as stuff comes up. This might also help others out down the road sometime.

I'm not the original owner of this bike so I don't really have any history on it before I got it. Due to how it ran I am going to assume it has stock pistons and compression. I'll be able to see what cam was installed once I get the current one out.

Basically I'm thinking to keep things relatively stock and from some reading an EV13 cam might be good to go with, but I'm open to suggestions.

For lifters I'm thinking either stock or S&S. Pushrods, I'm going to clean off the current adjustable ones and look them over closely to see if I can live with them once I get the other two removed.

Currently building up a shopping list and trying to figure out where to buy or order stuff from. I'll probably visit a couple local dealerships to get a feel of options and prices from them as well.

Oh yeah, one more thing, those little 12-point screws holding the lifters in place are a bear to get out. For the front one I couldn't find a socket to fit so ended up using a 1/4" boxend wrench. The rear ones look worse to get to, at least the one closest to the cylinders near where that bolt protrudes from the engine case.
 

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Hate to be discouraging Mike, but prob gonna need a new oil punp on that list. Flush the oil tank real good and blow high pressure air through the oil passages in the block in reverse of oil flow direction...Been there, just like you..Good Luck!
 

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Seeing the damage done I would think the ground up bits have already gone throughout the engine and maybe damaged other parts. Personally, I wouldn't feel right just repairing the obvious stuff. I would pull the engine and tear it all down to take a look at everything.
 

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Discussion Starter #19 (Edited)
Ouch, bummer. I'm still going to keep working my way in and will look closely at the oil in the tank. I guess I'm going to start pricing a complete overhaul as well. Like I just told one of the ladies in the shop who's husband rides, I might end up eating nothing but oatmeal for dinner for the next six months.

Time to start cleaning off the work bench and sell off some bicycles to make room for the project.

Edit: Eventually I was thinking of messing with the wiring and dash panel and extracting the CB radio and update some of that sort of stuff. If I've got to pull the engine then I might start moving that wiring plan up as well. I think mission creep has potentially arrived. Good thing I've still got a Buell to ride while the H-D is down.
 

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I'd be worried about rollers and debris from that lifter in the bottom end.

Factory re-man engines aren't a bad deal, you can get a new engine for less money than you wife has in her riding wardrobe. I'm not sure if they require dealership R & R to get advertised price, if they do you can probably find a dealer somewhere that will work with you on engine only.

Good luck.
 
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