Kawasaki engine

[shrodney]

I hope it's okay to post such a question here, since this is not skid steer related: I am working on a JD 777 Z-turn mower with a Kawasaki V-twin engine. When it gets hot, it gets what sounds like a slight backfire up through the carburetor when you engage the blades and gas comes out of the vent tube on the carburetor. If you shut it down for about 30-45 minutes, it will go again for about 30 minutes. We are having record heat here which may be a factor. It's a water-cooled engine and it's not losing any coolant or oil. The owner says it's happening on two other mowers of his as well. He thinks it's the gas, but I think otherwise (vapor lock?).

 

[OldMachinist]

It sounds like a valve problem. I don't know if the Kawasaki engine has hydraulic or mechanical lifters. If hydrauilic I'd try a little thicker oil and see if the problem goes away. If mechanical then they may need adjusted. Which model engine does it have?

 

[shrodney]

It sounds like a valve problem. I don't know if the Kawasaki engine has hydraulic or mechanical lifters. If hydrauilic I'd try a little thicker oil and see if the problem goes away. If mechanical then they may need adjusted. Which model engine does it have?

I don't know the engine model, but they are hydraulic lifters. I had one friend tell me that it sounded to him like perhaps a valve guide swelling and sticking the valve (probably the exhaust) and not allowing it to open all the way, causing the backfiring via the carb. Also, I checked the compression hot and it was 120 psi on one side and 105 psi on the other, which could also be caused by a sticking valve, not closing all the way. I'll do some more checking next week. Strange that it's happening on 3 mowers at the same time, though. Coincidence? I've read that Ethanol has been wreaking havoc on small engines. Perhaps.....

 

[OldMachinist]

I don't know the engine model, but they are hydraulic lifters. I had one friend tell me that it sounded to him like perhaps a valve guide swelling and sticking the valve (probably the exhaust) and not allowing it to open all the way, causing the backfiring via the carb. Also, I checked the compression hot and it was 120 psi on one side and 105 psi on the other, which could also be caused by a sticking valve, not closing all the way. I'll do some more checking next week. Strange that it's happening on 3 mowers at the same time, though. Coincidence? I've read that Ethanol has been wreaking havoc on small engines. Perhaps.....

I did a little searching for what model engine is in the 777 and found it should have a FD671D or FD750D and they both need regular valve adjustments. The min compression for those engines is 170 psi so both your cylinders are low. I have the service manuals for the most Kawasaki engines so after you find out which engine it is send a message to the email address in my profile and I'll send you a link where you can download it.

 

[shrodney]

I did a little searching for what model engine is in the 777 and found it should have a FD671D or FD750D and they both need regular valve adjustments. The min compression for those engines is 170 psi so both your cylinders are low. I have the service manuals for the most Kawasaki engines so after you find out which engine it is send a message to the email address in my profile and I'll send you a link where you can download it.

Thanks. I'll check it and get back to you.

 

[jerry]

Thanks. I'll check it and get back to you.

I I have used the product called “seafoam “ in 3 or 4 engines that seemed to have valve problems and it did help. I do think the gasoline now tends to build deposits in the engines. I don't know what it did but the engines ran better afterward.

 

[skidsteer.ca]

I I have used the product called “seafoam “ in 3 or 4 engines that seemed to have valve problems and it did help. I do think the gasoline now tends to build deposits in the engines. I don't know what it did but the engines ran better afterward.

OM
would you have a manual for the LX277 JD with a Kawi 17hp?
Mine has a anoying surge at idle, I found the carb loose and fixed that thinkin vac leak ro no avail and poured the seafoam to it too.
Ken

 

[OldMachinist]

OM
would you have a manual for the LX277 JD with a Kawi 17hp?
Mine has a anoying surge at idle, I found the carb loose and fixed that thinkin vac leak ro no avail and poured the seafoam to it too.
Ken

I have a John Deere LX service manual it doesn't cover your exact model but may be some help.
http://www.mediafire.com/file/o1qbfysikyao1zi/John-Deere-LX-Service-Manual.pdf
The info I have says the LX277 has a FH500V engine. Here are the links to the operator and service manuals.
http://www.mediafire.com/file/9qo2narjorvbu0m/17hp_FH500V.pdf
http://www.mediafire.com/file/1oat518vdpefnbo/17hp_FH500V_oper.pdf
If the engine model is different let me know.
Here's a link to the online LX277 operators manual.
http://manuals.deere.com/cceomview/OMM142612_D7/Output/OMM142612_C016.html