1977 Cb550f blue smoke
- Thread starter Leetillman351
- Start date
datadavid
Over 1,000 Posts
I agree. Plus you really do not want to rush engine work so please dont try to squeeze something like that into a weekend.
Does it smoke continually or do the smoking increase after you loaded the engine in gear then pull and drop the clutch and engine brake? If it increases with sudden engine braking it is a way to tell if its the rings rather than valveguide leaks.
Does it smoke continually or do the smoking increase after you loaded the engine in gear then pull and drop the clutch and engine brake? If it increases with sudden engine braking it is a way to tell if its the rings rather than valveguide leaks.
Leetillman351
Active Member
Yall are right, I should take the time and do it right while I'm there. I'll inspect the rings and cylinder walls.
I ordered a full top end rebuild kit from DCC so I might as well utilize it all.
Anything else I should go ahead and order and replace? I head can chain and all the rubbers, it that a quick switch or does replacing the cam chain require more disassembly?
I ordered a full top end rebuild kit from DCC so I might as well utilize it all.
Anything else I should go ahead and order and replace? I head can chain and all the rubbers, it that a quick switch or does replacing the cam chain require more disassembly?
If it's an endless chain, the "proper" way is to disassemble the entire engine and remove the crank. I know of guys who use a chain breaker and rivet the chain back together, but that doesn't sit too well with me. That said, I don't know of any failures for this approach (doesn't mean they don't exist, though, it's just that I don't know of any).
there is nothing wrong with using a chain with a master link :
it is perfectly safe to think otherwise is kinda like being superstitious
you dont knead a chain breaker just carefully grind the head offa the 2 offending link rivets and pri it off , easy peesy japaneasy
you don'tnead a chain riveting tool neither, a good heavy backup and a small ball pein hammer is all , carry on
it is perfectly safe to think otherwise is kinda like being superstitiousyou dont knead a chain breaker just carefully grind the head offa the 2 offending link rivets and pri it off , easy peesy japaneasy
you don'tnead a chain riveting tool neither, a good heavy backup and a small ball pein hammer is all , carry on
AFAIK, you can remove the head and cam without breaking the cam chain. The head can be removed, valves removed, inspected, cleaned up and rebuilt with new guide oil seals in a weekend if you have parts and tools lined up.
It is highly likely that at least one valve seat will be pitted from sitting for so long and that would require a trip to an auto engine machine shop.
Worn oil rings don't make much difference to compression but check it anyway and do a dry test and wet test (small amount of oil down the plug hole) and see what the numbers are like. If you can do a leak down test, that would give some indication of where the air is leaking out and that would be very useful info.
If the rings are shot or a bore is rusty or scored, the cylinder has to come out but the motor can stay in the frame. Pistons and rings are available on line but that takes it past a weekend job in all probability.
It is highly likely that at least one valve seat will be pitted from sitting for so long and that would require a trip to an auto engine machine shop.
Worn oil rings don't make much difference to compression but check it anyway and do a dry test and wet test (small amount of oil down the plug hole) and see what the numbers are like. If you can do a leak down test, that would give some indication of where the air is leaking out and that would be very useful info.
If the rings are shot or a bore is rusty or scored, the cylinder has to come out but the motor can stay in the frame. Pistons and rings are available on line but that takes it past a weekend job in all probability.
Leetillman351
Active Member
Hmm with that said I think I'll keep the cam chain as is and just replace the rubbers. Replacing that wouldn't sit to well with me
Leetillman351
Active Member
Teazer that's good information thanks,
When I get the head off I'll post pics of the cylinders and hopefully you all can help me determine if I need to have them machined etc.. However before I tear it all down j will do a compression test, if it checks out then I will just do the seals and call it quits for the time being, I'll still pull the head to make valves easier
When I get the head off I'll post pics of the cylinders and hopefully you all can help me determine if I need to have them machined etc.. However before I tear it all down j will do a compression test, if it checks out then I will just do the seals and call it quits for the time being, I'll still pull the head to make valves easier
If the cam chain has to be cut for some reason, treat the motor like a patient in surgery with only the part being cut visible and all the rest carefully covered up to keep grinding dust out.
"split" cam chains are cheap and easy to fit and perfectly safe to use. All our race motors use split inks on cam chains and no failures in 40 years even when cam chain adjusters broke up and valves got bent etc.
"split" cam chains are cheap and easy to fit and perfectly safe to use. All our race motors use split inks on cam chains and no failures in 40 years even when cam chain adjusters broke up and valves got bent etc.
Leetillman351
Active Member
Could someone point me in the right direction for piston rings?
I already ordered a top end rebuild from DCC but need some rings
I already ordered a top end rebuild from DCC but need some rings
Leetillman351
Active Member
Just got the valve cover off to expose the cam, I'll get the head and jug off tomorrow and take it somewhere to have it measured. Hopefully I'll have a measurement tomorrow for you guys so you can give me some advice on what I should do. (Bore and get larger rings, just a hone and new rings, etc..)
I really appreciate yalls help, this is my first top end job on an old engine, just want to do it right!
I really appreciate yalls help, this is my first top end job on an old engine, just want to do it right!
Leetillman351
Active Member
I got out of my calculus test a little later than expected last night so I wasn't able to get the heads off yet, went by autozone to get a 1/4 extender this morning before class so after this class I'll get the head off and jug and I'll FINALY be able to measure the sleeves.
I'll post pictures with the heads off ASAP, thanks again fellas!
I'll post pictures with the heads off ASAP, thanks again fellas!
Leetillman351
Active Member
Nice surprise! (Sarcasm)
When I lifted the jug I found rocks and sand at the base of the bolts, luckily I was able to move it all away lightly using a tooth brush.
The sleeves appear to be ok with no scoring, the lines you see in the picture are from the reflection of the wood.
Can autozone measure the bore? Or will I need to take it to a shop?
When I lifted the jug I found rocks and sand at the base of the bolts, luckily I was able to move it all away lightly using a tooth brush.
The sleeves appear to be ok with no scoring, the lines you see in the picture are from the reflection of the wood.
Can autozone measure the bore? Or will I need to take it to a shop?
Attachments
no not autozone
take it to a machinist that can work on this stuff and pay them to check every bore, take the pistons in with you as well,mark them for what hole and show up with the specs from the factory service manual
it can be tricky pulling wrist pins a lil bur-ridge get knurled at the edge of the clip groove sometimes after taking out the clip i will use an exacto blade to remove the bur sometimes just heating up the piston does the job though
do not get carried away trying to "clean" the pistons you can easily do more damage than good :-\ all you need to do,really, is gently remove the loose stuff from the tops, do not polish the tops, do not do anything to the skirts
take it to a machinist that can work on this stuff and pay them to check every bore, take the pistons in with you as well,mark them for what hole and show up with the specs from the factory service manual
it can be tricky pulling wrist pins a lil bur-ridge get knurled at the edge of the clip groove sometimes after taking out the clip i will use an exacto blade to remove the bur sometimes just heating up the piston does the job though
do not get carried away trying to "clean" the pistons you can easily do more damage than good :-\ all you need to do,really, is gently remove the loose stuff from the tops, do not polish the tops, do not do anything to the skirts
