My 92 FXSTC's carb was binge eating dirt again. Head removal?
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My 92 FXSTC's carb was binge eating dirt again. Head removal?
Well long story short I lost it and she ended up sliding in grass. Among other issues it looks like my carb was binge eating dirt/fertilizer. When I took it off I noticed a small amt of sand/dirt/dust on the side connected to the intake. I stuck my finger down both sides of the intake and it had a very light sand/dirt coating so it appears that a little made it past/under the butterfly. I don't want to destroy my motor so how do I make sure I'm not putting any dirt/sand thru it? Is my next step removing the heads, cleaning them up, and checking for anything on top of the pistons?
Since if you are trying to see what really went in and I assume you think it was running while down, I would pull the carb first and see what is on down that way. It needs to be done anyway and may save you some time. Just how did all that get past the air filter?
A FI bike would have shut off since it has a bank angle switch in the signal light and or signal light alarm system that kills fuel pump. Does the last round of Harley carb bikes have that say for the ignition? Know my old 2005 1100 V-Star Yamaha had two carbs and had a bank angle circuit.
Last edited by Jackie Paper; 07-14-2019 at 07:09 AM.
Since if you are trying to see what really went in and I assume you think it was running while down, I would pull the carb first and see what is on down that way. It needs to be done anyway and may save you some time. Just how did all that get past the air filter?
A FI bike would have shut off since it has a bank angle switch in the signal light and or signal light alarm system that kills fuel pump. Does the last round of Harley carb bikes have that say for the ignition? Know my old 2005 1100 V-Star Yamaha had two carbs and had a bank angle circuit.
No, I'm not concerned it was running when it went down. It was in gear, so when I was thrown off the bike cut off. I had a forcewinder intake on it; when the bike was sliding the k&n cone filter was destroyed and intake started acting like an ice cream scoop for the dirt. I already took the carb off, ran my finger down the intake manifold, and it was slightly gritty. I plan on taking off the manifold today to get a better look. In the event there is a little dirt in there would air be sufficient to clean it out? In order to take off the heads I have to rotate the motor; just worried that by opening the valves it will lead to stuff getting deep in there.
I would not worry about it. What if it takes some life out of motor.
Pulling it apart is 3/4 of an overhaul. If had to pull it apart, I would touch up valves, crosshatch and re-ring it.
Once junk gets in top in, it would be really hard getting it out of the small area between top of piston and first ring.
Got the intake manifold off and took a look + swiped my fingers. There was a few grains/a little grit but not as bad as I thought. I was thinking of just using air on it for now but getting a bore scope to make sure nothing is in the cylinders.....
Why do you need to rotate the engine to remove cylinder heads?
You need to rotate the engine when reinstalling rocker supports, but not when you remove them, just loosen the bolts evenly.
If the engine has low mileage, it may be worth a set of gaskets to go ahead and disassemble and clean it up.
If it is a high mileage motor, I would just blow it out, clean the carb and go...
I thought you were supposed to rotate the motor to relieve pressure from the rocker arms before removal. I ended up taking off the head to check out the top of the piston for dirt/sand. There was a cple grains of sand + very light debris. The motor definitely was not running when the dirt was introduced to the intake.
It was suggested that I continue with disassembly and remove the cylinder, clean it up good, and replace base gaskets (even though they probably have 500-1k on them).
As far as the piston I was told to remove the rings, clean the grooves good, and reinstall rings. The rings maybe have 3k on them. Can I get away with reusing or do I need new ones. Also, do I have to rehone cylinder if I'm using the same rings and there's no damage?
Also, is the amount of carbon on the head/valves normal? I plan on cleaning it up a bit with a wire brush but was curious.
The rings will never match up where they seal on the bottom side of the ring groove. Also very fine lines in cylinders. It would be best to re-ring and crosshatch. However, doing that probably removes .0003 to .0005 at a minimum from cylinders. Lot of miles.
Just my opinion and what I have seen it a lot of in-frame rebuilds I have done. Also what I have seen and done over the years, I would have never gone that far (unless it was an airplane..Haa.).
My first rebuild was an air-cooled 62 Corvair 150 HP turbocharged 4 cylinder back in 1966. Cut the ridges by hand out of the 4 cylinders with a high-speed tool used on a lathe. My last will probably the Jeep you see here.
Last edited by Jackie Paper; 07-19-2019 at 12:55 PM.
07-13-2019, 10:22 PM
My 92 FXSTC's carb was binge eating dirt again. Head removal?
.Haa.).