Wee Hooker
Chief Petty Officer
- Joined
- Sep 11, 2005
- Messages
- 618
Hi all, it's been a while since I participated in these forums . Hope you've all been well!
So the subject motor came to me from a friend and wont' run or even "fart . It also seems to "pull" to easily. I have already verified that it has spark and fuel but it tests only 35 psi compression (even after 5-6 pulls). I know from research (and testing my similar Tohatsu/Nissan 5 hp ) that it should be up near 85 psi or so. BTW, This same motor ran strong just a year ago before a friend took it. Said he started it after winter storage this spring and it ran for 5 seconds and quit. Never to start again.
So in an effort to see if it is a broken/stuck ring, I've stood the motor plug hole up, shot some SAE 30 oil in there to wet the rings (only) and retested. It gives me only 50 psi after that. ( i.e not a whole lot of improvement.) My guess here is that it's not rings and likely a head gasket but I'm not sure. I'm pretty good with electrical and fuel troubleshooting and repair but fairly green with compression. Can I leak test the head gasket?
So, any advice on how to further troubleshoot would be helpful. Also If it is a head gasket, it doesn't look too bad but that is admittedly unpracticed territory for me. IS the gasket set hard to find? Tricks/ Don'ts...?
Thanks in advance!
Dave
So the subject motor came to me from a friend and wont' run or even "fart . It also seems to "pull" to easily. I have already verified that it has spark and fuel but it tests only 35 psi compression (even after 5-6 pulls). I know from research (and testing my similar Tohatsu/Nissan 5 hp ) that it should be up near 85 psi or so. BTW, This same motor ran strong just a year ago before a friend took it. Said he started it after winter storage this spring and it ran for 5 seconds and quit. Never to start again.
So in an effort to see if it is a broken/stuck ring, I've stood the motor plug hole up, shot some SAE 30 oil in there to wet the rings (only) and retested. It gives me only 50 psi after that. ( i.e not a whole lot of improvement.) My guess here is that it's not rings and likely a head gasket but I'm not sure. I'm pretty good with electrical and fuel troubleshooting and repair but fairly green with compression. Can I leak test the head gasket?
So, any advice on how to further troubleshoot would be helpful. Also If it is a head gasket, it doesn't look too bad but that is admittedly unpracticed territory for me. IS the gasket set hard to find? Tricks/ Don'ts...?
Thanks in advance!
Dave
