Loss of power... exhaust leak ? or burnt valve? (1 Viewer)

[MR.FJ60]

Well guy's I recently had this happen to me. The 2F had been running with and exhaust leak for a while and finnally the other day I felt a sudden loss of power and I don't think it's the exhaust leak anymore. She'll run rugh at idle and run fine after the RPMs get up and going. Anyone had any issues like this? I haven't had time to get in there yet. Thanks in advance.

 

[RredFJ40]

Do you have to run it with the choke out to keep it running smooth?

I blew the head gasket between #'s 3 and 4, so I had very low compression in those two.

First thing I'd do is a compression check, dry then wet to tell you if it's a valve problem or otherwise.

 

[MR.FJ60]

Do you have to run it with the choke out to keep it running smooth?

I blew the head gasket between #'s 3 and 4, so I had very low compression in those two.

First thing I'd do is a compression check, dry then wet to tell you if it's a valve problem or otherwise.

Yes pretty much, Hopefully I can get her in this weekend to the shop and check her out closer and do a compression check for sure. thanks

 

[clems06]

Rred,

I realise this may be a stupid question but, what do you mean by a wet or dry compression check? I have a 62, that i have changed plugs, wires, cap & rotor, air filter, and fuel filter and still have lacking power. I notice a smell of petrol sometimes which concerns me. Also, if i drive for a couple hours interstate, my check engine light comes on. I am thinking to change the O2 sensors next, do you suggest this approach?

thanks,

robert

 

[roscoFJ73]

Rred,

I realise this may be a stupid question but, what do you mean by a wet or dry compression check? I have a 62, that i have changed plugs, wires, cap & rotor, air filter, and fuel filter and still have lacking power. I notice a smell of petrol sometimes which concerns me. Also, if i drive for a couple hours interstate, my check engine light comes on. I am thinking to change the O2 sensors next, do you suggest this approach?

thanks,

robert

There are no stupid questions
A wet compression test involves putting a teaspoon of oil into the combustion chamber via the sprk plug hole.
You do the dry(without oil) comp test 1st then the wet.

If the comp goes up after the wet test you can assume the rings are worn as the oil has helped seal the gap between cyl and rings.

If there is no change in the comp reading then you can assume the valves are worn as the oil will not seal the valve slop.
I suppose this could also mean a bad head gasket

 

[billmc]

Rred,

I realise this may be a stupid question but, what do you mean by a wet or dry compression check? I have a 62, that i have changed plugs, wires, cap & rotor, air filter, and fuel filter and still have lacking power. I notice a smell of petrol sometimes which concerns me. Also, if i drive for a couple hours interstate, my check engine light comes on. I am thinking to change the O2 sensors next, do you suggest this approach?

thanks,

robert

If you've never changed your O2 sensors you should probably do so in any case. The FSM calls for their replacement at 80 or 90K miles as part of regular maintainence.

Bill

 

[Tinker]

Leak-down test is better than compression - it'll tell you which rings and/or valves.

 

[cabron]

Also hook up a vacuum gauge, it can tell you a whole lot about whats going on. I hook mine to brake booster on my 40

 

[brett76]

also make sure that part of the leak is not coming from the egr recovery tube anywhere. if that is leaking it will suck too much clean air into the egr system and run like @&@&@&@&. thats what mine was doing. you can check with some rubber tubing and poke it around and find exactly where all your leaks are coming from