Steve Saunders Goldwing Forums banner
1 - 20 of 89 Posts

·
Registered
1978 GL1000 cafe
Joined
·
57 Posts
Discussion Starter · #1 · (Edited)
Hello again,
Just did a compression test and found strange confusing result? on the right side 1&3 I have a respectable 135lbs but on the left side I have 75lbs on #2 and 85 on #4 with a strange plunking exhaust noise from the cylinder being tested, I know this involves checking the valves next probably should have done that first, considering the right side 1&3 are good seems strange that both cylinders on the left are so similarly bad with the strange noise compared to the right side of the engine? , seems odd, could it be a blown head gasket? checked oil is clean no water, same for coolant it's normal? any feed back would be appreciated, Im at a loss with limited backyard mechanics knowledge , Im going to wait for replies and suggestions before I pull valve covers, I'm sure this isn't good news but if someone can shed some light here will help going forward, any suggestions! Thank you.
 

·
Administrator
Joined
·
28,657 Posts

·
Registered
1978 GL1000 cafe
Joined
·
57 Posts
Discussion Starter · #6 · (Edited)
Wow I missed that one, makes sense, will check in that direction, thank you,
cutwater.
Thanks again for advice I have been reading about timing belt skipping timing and it all fits my symptoms, the engine started fine and ran ok other than a slight miss all was well, I did find 3&4 running lower temp, that prompted me to check compression, that was about it, the good news is no horrible noises or flaming parts spitting out the tail pipe, hope I dodged the dreaded catastrophic belt failure and valve to piston collision, that sounds like something I would notice right away, I get nervous when I hear the B word, .. is that a fair assessment?
.appreciate the help
cutwater.
 

·
Administrator
Joined
·
28,657 Posts
If it had a valve to piston collision there wouldn't be any compression on those cylinders. Just a tooth or 2 off would cause those symptoms and not be enough to bend valves.
 
  • Like
Reactions: limpy45

·
Registered
Joined
·
1,930 Posts
The knocking is a little concerning. You obviously don't have a catastrophic failure, but if there was any contact, the head will likely need to come off. Hopefully you dodged a bullet and it's just off a tooth or two. New belts and you're back in business.
 

·
Registered
1978 GL1000 cafe
Joined
·
57 Posts
Discussion Starter · #9 ·
If it had a valve to piston collision there wouldn't be any compression on those cylinders. Just a tooth or 2 off would cause those symptoms and not be enough to bend valves.
I definitely still have compression, it actually ran pretty well, now starts the wrench work and new belts! thanks!
cutwater
 

·
Registered
1978 GL1000 cafe
Joined
·
57 Posts
Discussion Starter · #10 ·
The knocking is a little concerning. You obviously don't have a catastrophic failure, but if there was any contact, the head will likely need to come off. Hopefully you dodged a bullet and it's just off a tooth or two. New belts and you're back in business.
Im getting a real education here, it didn't have a knocking noise more like a slight mis fire that was hard to even detect, actually ran pretty well considering the lack of compression,
I did notice by feel a pronounced lack of back pressure from left side exhaust, when I removed the exhaust header noticed wet unburned fuel in the pipe and plugs,
this all makes sense now, need to sharpen my mechanical skills purchase new belts and get to it, I will follow the book and very good video bronco37 posted, thanks for the help here I was off track with my amateur diagnosis , thank for the redirection, big help!
cutwater
 

·
Registered
1978 GL1000 cafe
Joined
·
57 Posts
Discussion Starter · #11 ·
Im getting a real education here, it didn't have a knocking noise more like a slight mis fire that was hard to even detect, actually ran pretty well considering the lack of compression,
I did notice by feel a pronounced lack of back pressure from left side exhaust, when I removed the exhaust header noticed wet unburned fuel in the pipe and plugs,
this all makes sense now, need to sharpen my mechanical skills purchase new belts and get to it, I will follow the book and very good video bronco37 posted, thanks for the help here I was off track with my amateur diagnosis , thank for the redirection, big help!
cutwater
appreciate a little more assistance , Timing covers removed timing at TDC, I was expecting to visually see the timing belt off by a tooth or two but spot on, checked three times, belts are spot on! am I correct in thinking I would see the timing error? everything looks on the money$ ... suggestions appreciated . cutwater.
 

·
Registered
1978 GL1000 cafe
Joined
·
57 Posts
Discussion Starter · #12 ·
The knocking is a little concerning. You obviously don't have a catastrophic failure, but if there was any contact, the head will likely need to come off. Hopefully you dodged a bullet and it's just off a tooth or two. New belts and you're back in business.
appreciate a little more assistance , Timing covers removed timing at TDC, I was expecting to visually see the timing belt off by a tooth or two but spot on, checked three times, belts are spot on! am I correct in thinking I would see the timing error? everything looks on the money$ ... suggestions appreciated . cutwater.
 

·
Registered
1978 GL1000 cafe
Joined
·
57 Posts
Discussion Starter · #14 ·
Can you do a leakdown test?
You can pull the valve cover and see if any valves are sticking.
I guess the fact the belts are in time means Im off on a new adventure, I dont have the tools for a leak down test, if needed I will get, for now I just went out and cranked it over all valves are working perfect oil is pumping, everything is very clean, any ideas where we are going? what should I be looking for? thanks for all the great advice! cutwater...
 

·
Administrator
Joined
·
28,657 Posts
Pull the left valve cover, with the crank at #1 TDC you should see the top of the cam lobes on #2 being equal distance from the end of the rocker arms. Wondering if the key in the cam might be worn causing the timing to be off. I bought an 1100 with a knocking noise, turned out to be the bolt holding the pulley was loose.
 

·
Registered
1978 GL1000 cafe
Joined
·
57 Posts
Discussion Starter · #16 ·
Pull the left valve cover, with the crank at #1 TDC you should see the top of the cam lobes on #2 being equal distance from the end of the rocker arms. Wondering if the key in the cam might be worn causing the timing to be off. I bought an 1100 with a knocking noise, turned out to be the bolt holding the pulley was loose.
Just got your message on way to bed but had to try this, at #1 TDC the lobes on #2 exhaust and intake are equal off the top of the lobe more on the side of the lobe but equal if I'm following correctly , I never had a knock of any kind no unusual noises at all, valves are not sticking all looks normal other than both at low 75 and 77 lbs compression and a noise from both cylinders as it cranks from the escaping compression in the exhaust, Im guessing does not sound like the right side has to be the escaping compression ? I'm at a loss here for ideas now , any suggestions I will follow and report, Thanks again!,
 

·
Senior Member
Joined
·
1,870 Posts
Please note: The ignition timing would be incorrect on all cylinders if the timing belt had jumped on the left side, as it is the left camshaft that drives the ignition system. (I assume we're talking about a GL1000?).
 

·
Administrator
Joined
·
28,657 Posts
Please note: The ignition timing would be incorrect on all cylinders if the timing belt had jumped on the left side, as it is the left camshaft that drives the ignition system. (I assume we're talking about a GL1000?).
True if it jumped, which is unlikely, but if put together wrong the timing can be compensated for.
 

·
Registered
1978 GL1000 cafe
Joined
·
57 Posts
Discussion Starter · #20 ·
Please note: The ignition timing would be incorrect on all cylinders if the timing belt had jumped on the left side, as it is the left camshaft that drives the ignition system. (I assume we're talking about a GL1000?).
Yes, 78 GL1000 the belts are spot on as well as valve lash, Im scratching my head because I am out of ideas, it's here I'm just not seeing it, any ideas I will follow up! thanks again.
cutwater
 
1 - 20 of 89 Posts
Top