slumlord
New member
03viperguy I don't have any merc parts sold that one more than 20 years ago.
PZ 1
Member
- Joined
- Mar 12, 2005
- Messages
- 987
The low compression needs to be fixed. It might not be the entire cause, but there is a problem there somewhere. Measure the piston and cylinder.
03viperguy
Moderator
so I tested the coil, good secondary, bad primary readings. new coil on the way, hopefully that fixes it
slumlord
New member
Pz1 agree on the compression issue, main reason for this thread. Thought there may be other known reasons why compression is low. That cylinder was bored and piston assembly replaced. I will check it
To make sure it was not over bored? Just seems odd the comp
has not changed from starting this whole thing.
To make sure it was not over bored? Just seems odd the comp
has not changed from starting this whole thing.
stanage
Member
stator resistance testing
I would also be tempted to check the resistance of the stator coils.... sounds like perhaps the low speed coil is failing. Just found out yesterday, my coils fail once the sled is warm, not cold! Go Figure!
I would also be tempted to check the resistance of the stator coils.... sounds like perhaps the low speed coil is failing. Just found out yesterday, my coils fail once the sled is warm, not cold! Go Figure!
03viperguy
Moderator
yeah, the windings warm up, expand, and possibly crap out.
03viperguy
Moderator
so anyone have anymore ideas? I changed coils and wires, no difference. maybe rust on the flywheel or something?
slumlord
New member
Start a different thread. I started this to try and figure out if others had similar problems with low compression and what the solution turned out to be. Not your electrical problems.
03viperguy
Moderator
was trying to see if yours was solved as maybe mine would be the same issue and it would solve it. then anyone searching later would find a solution.
ventureguy
New member
This may sound silly but have you checked your fuel filter or
replaced it.
My 485 Venture holed a piston last winter and I rebuilt it and then
it wouldn't run properly. It sounded like it was running on one cylinder
and was slow to rev. I had gas in the carb bowls and I had cleaned
the carbs 3 times. When I pulled the filter it was black instead of yellow.
Once changed it instantly changed(even my wife could tell).
Its an easy and cheap try.
replaced it.
My 485 Venture holed a piston last winter and I rebuilt it and then
it wouldn't run properly. It sounded like it was running on one cylinder
and was slow to rev. I had gas in the carb bowls and I had cleaned
the carbs 3 times. When I pulled the filter it was black instead of yellow.
Once changed it instantly changed(even my wife could tell).
Its an easy and cheap try.
03viperguy
Moderator
that is an excellent idea. and simple
I have this exact same issue with an 86' phazer, the only difference I have compression readings of 125/126 on a cold engine, which should be plenty. When it runs it feels sometimes like the second cylinder will kick in periodically if I play with the throttle a lot.
But when I pulled the plugs the clutch side looks good, maybe a bit rich. The mag side is clean the plug looks like I just took it out of the package! Carbs have been cleaned many times, the airbox I JUST installed and I had it apart to clean, and I have spark. What else could it be?? The only thing I havent checked is blocked passage in the fuel line, but there should still be oil on the plug right? Since the phazers squirt the oil into the carb boot just before reeds?
Or could it possibly be bad reeds sticking closed??
But when I pulled the plugs the clutch side looks good, maybe a bit rich. The mag side is clean the plug looks like I just took it out of the package! Carbs have been cleaned many times, the airbox I JUST installed and I had it apart to clean, and I have spark. What else could it be?? The only thing I havent checked is blocked passage in the fuel line, but there should still be oil on the plug right? Since the phazers squirt the oil into the carb boot just before reeds?
Or could it possibly be bad reeds sticking closed??
sleddineinar
VIP Member
brade07 said:I have this exact same issue with an 86' phazer, the only difference I have compression readings of 125/126 on a cold engine, which should be plenty. When it runs it feels sometimes like the second cylinder will kick in periodically if I play with the throttle a lot.
But when I pulled the plugs the clutch side looks good, maybe a bit rich. The mag side is clean the plug looks like I just took it out of the package! Carbs have been cleaned many times, the airbox I JUST installed and I had it apart to clean, and I have spark. What else could it be?? The only thing I havent checked is blocked passage in the fuel line, but there should still be oil on the plug right? Since the phazers squirt the oil into the carb boot just before reeds?
Or could it possibly be bad reeds sticking closed??
Is the mag side case full of gas? Mine was like that recently, the clutch side plug looked normal but the mag side plug was clean, almost like it was fresh out of the package. I opened the reed cages to see if the reeds were damages and discovered that the mag side was full of gas.