Poor running after cam-belt replacement

[Sleazy Rider]

Installed Poor-Boy alternator kit and decided to replace the belts while I was at it. Checked and double checked and triple checked to make sure all marks were aligned as per manual. (replaced belts many times on my GL1000's and 1100's) This bike is a "new to me" 1986 GL1200A. It ran beautifull before I tore it apart to install the ext. alternator and replaced the old belts. I'm using NAPA belts for the replacement, the belts that come out were OEM Honda's. It idles OK @ 1000 RPM and fires right up, but is slow to respond to throttling up and "pops" and back fires thru the exhaust. Cyls #1 and #3 barely feel warm to the touch (exhaust headers), while #2 and #4 get really hot in a hurry. In neutral I can rev her up to red line, under a load she almost dies when I try to take of in 1st gear. Have to slip the clutch to keep from stalling out. No power and lots of pinging and backfiring. I'm just "plain out of ideas" of what I did to the poor girl. Nothing was changed except the timing belts and she run wonderful before. HELP?!?!

 

[dan filipi]

I would do a compression test next.
That will tell us if the valves are ok first off.

Is fuel delivery ok?

 

[joedrum]

do you think you may have mess up the front ignition pickups the 86 1200 has right there where the belt go on the crank ....all i can think of at the monemt that might of mess the ignition up

 

[backlander]

just bought new set belts but I'm a little gunshy till this gets sorted out. got to be a common denominator here somewhere. Looked like simple job after watching littlebeavers video.

 

[rock42]

wonder if it is the same thing on my gl1000, the symtons sounds the same hope we all get the problem solved.

 

[joedrum]

hmmmmmmm i thinkinking carb trouble to the cv slides from backfire maybe rock...sliders could be broke or leaking from trauma of backfire and not sliding in sync at all causing high rpm failure to run good

 

[mcgovern61]

I am under the opinion that the timing marks may be correct on the cam pulleys, but is it possible the crank moved while you were putting the belts on? That type of change in timing is normally directly related to crank position. Cams position on valves (and timing belt marks) might be spot on, but is the crank correct? (One tooth off on crank is a lot different than one tooth off on the cam pulley.)

 

[AApple]

do you think you may have mess up the front ignition pickups the 86 1200 has right there where the belt go on the crank ....all i can think of at the moment that might of mess the ignition up

Now you guys don't laff, since I can't seem to get mine runnin, but...IF the ignition triggers off of the crank on the 1200, as Joe says, it would seem that it could possibly be something with that that is causing this problem. Assuming, of course, that the timing on the belts is correct.

 

[Sleazy Rider]

Thanks for all the good inputs to the problem I'm experiencing. Re-did everything again last night. (have done that now 6 or 7 times???I think, I lost count.LOL) Everything, checks out great. By itself and in itself but as soon as she's back together.....same problem. Just doesn't make sense. Thinking about getting some BBQ starter fluid and having a bon-fire. (not really). :head bang:

 

[AApple]

Thinking about getting some BBQ starter fluid and having a bon-fire. (not really). :head bang:

I know the feelin....btdt....

Here's the page from the Honda Service Manual for the 1200. Be sure you are using the correct marks on the pulleys...there are two real close together...lots of folks have confused one for the other, and been off a couple of teeth. Even tho you've done them before, it never hurts to make sure...

 

[Sleazy Rider]

Well, Cylinders 1 and 3 are not working. I do get spark in them from the coils. But, it's like theyre 180 degrees out. How can that be? The crank is at the "T-1" mark, both cam pulley's are right on the mark, the "up" at 12 o'clock. Do I need to take the cam belt off the right head (#1 and 3) and rotate the crank 1 whole revolution (360 degrees) and re-install the right bank cam belt? Could it be that the #1 is at TDC on the exhaust stroke instead of the compression stroke? Eventhough the crank is at T-1???
Will I damge the valves is I turn the crank 360 degrees without the right cam belt on? Please, give me some good news.

 

[joedrum]

you need to go to t2 on that side thats not firings ....you need to pull the plugs ...turn the motor by hand on the crank bolt slowly till you can tell the piston is haftway down ...one piston way down all piston hath way down ...then take the belt off on bad side .....then turn cam pully as close to timing mark as possible ...then turn motor to t2 possition and put belt back on ....it might take a few times to get it right 1200 are a little nasty with the hydro heads ....

if you get it then turn motor over slowly with crank bolt to check for hitting of the valves do it more than once many time till your confident its not hitting .....

also go to the nuetral spot on both sides where the cam is free and readjust belt tensioner to right deflection one sid e then tuen to otheside free spot and do the same ....from there your good to go id say :mrgreen:it is 180 degree out

 

[Sleazy Rider]

Thanks Joe. Guess, I'll tear her down again and give that a try. :beg:

 

[joedrum]

ask any question along the way this is a huge job to get righ or pay dearly if you mess up you have been lucky up to now .....no fudge zone what so ever ...take pics if you can

 

[dan filipi]

I don't see how cam timing can be 180 out if "UP" is UP because the cam gears are locked in their position with a keyway.
There is no way to be 180 out if the crank is at T1 and the "UP" is UP.

 

[mcgovern61]

I don't see how cam timing can be 180 out if "UP" is UP because the cam gears are locked in their position with a keyway.
There is no way to be 180 out if the crank is at T1 and the "UP" is UP.

It can if the crank was out 180. T1 then looks right but it is out 180. Gotta make sure the piston is TDC and T1 mark.

 

[dan filipi]

I don't see how cam timing can be 180 out if "UP" is UP because the cam gears are locked in their position with a keyway.
There is no way to be 180 out if the crank is at T1 and the "UP" is UP.

It can if the crank was out 180. T1 then looks right but it is out 180. Gotta make sure the piston is TDC and T1 mark.

Wait.....T1 is T1, it's a full revolution.......init?......Yes it is. I looked at the crank, it has to be.
Gotta think on this.

 

[backlander]

two revs to complete the cycle, intake and exhaust, crank has to be at TDC of compression stroke to be in time, so it can be 180 out

 

[Sleazy Rider]

It's a 4-stroke. 2 revolutions of the crank for the 4 strokes. Piston has to be @ TDC on the compression stroke for the timing to be right. But piston will also be on TDC at the end of the exhaust stroke. Right?? Crank turn twice a full 360 degrees for each cam to turn once a full 360 degrees.??
I get spark at Cyl's 1 and 3 but at the wrong time.

 

[dan filipi]

Ok, T1 is T1. There's no 2 way's about that.
If there was I'd have surely been 180 out more than once with as many times as I've had the cams and heads off and these engines split open.

True the cams turn 1/2 speed but they still arrive at the same place in a full revolution.

Picture this while rotating the engine:

Crank at T1, both cams UP
Crank at T2, both cams down
Crank at T1, both cams UP

I just know I'll be thinking about this when my wife and I go out for our anniversary dinner :head bang: