1982 Johnson Seahorse-No Power Under Load

[seahorseinchatt]

I have a 1982 Johnson Seahorse 7.5 HP Model J8RCNR. After sitting for a couple of months it would not start. Had been running fine. Isolated problem to no fuel to the cylinders. I rebuilt the carb and replaced and gapped the spark plugs. The motor cranked right up and ran through all rpms. I took it out to the lake and as soon as I engage the prop it barely lugs around. Per advice in this forum I recleaned the carb including blowing it with compressed air. Same result-runs good until you put it in gear. I have a firm fuel bulb and checked that both cylinders are firing. I really need some help getting me back on the water while the fish are biting. Any advice? Thanks=Wayne

 

[Tim Frank]

Re: 1982 Johnson Seahorse-No Power Under Load

Have you drained/refilled the lower unit oil?
If so, what did the old oil look like?
You may have a lower unit problem.

 

[Rick.]

Re: 1982 Johnson Seahorse-No Power Under Load

After replacing the carb. you need to do a linc and sync. The procedure is in the manual. Have you done that? What do your plugs look like after trying to open the throttle? are they overly wet, dry or about normal? Rick.

 

[tashasdaddy]

Re: 1982 Johnson Seahorse-No Power Under Load

did you remove and clean the high speed jet in the bottom of the carb bowl, did you adjust the carb afterwards? all this is covered in the top secret file at the top of the J/E forum.

 

[seahorseinchatt]

Re: 1982 Johnson Seahorse-No Power Under Load

Thanks for the replies guys. I checked my lower unit oil early on and the fluid is a translucent dark brown. I am going to go change that out this weekend. From what I understand there is not much of a link-n-sync with this carb except for the low speed needle--which I did. This carb doesn't have a high speed needle-just an orifice with a high speed orifice plub (screw on cover with an orifice) which was cleaned and blown out. If I'm wrong about the link-n-sync please let me know. The plugs are wet but not drenching wet. I suspected at one point that my bottom cylinder was not firing. I do have oily discharge through the exhaust. But in the barrel, I ran the motor and removed the spark plug wire one at a time and it continues to run. Could I have a weak coil that doesn't fire right under load? I don't know if this is a clue or not, but when I remove the spark plug wire, I get an arc from the coil to the wire, but there is no arc when it is reconnected. I'll check out the top secret file about ajusting the carb. Thanks for your help.

 

[Rick.]

Re: 1982 Johnson Seahorse-No Power Under Load

Hi there. You should not be getting an arc from the coil to the wire even if it is removed from the plug. That could be your problem for sure. Connected to the plug your probably leaking some of the spark and getting a weak spark to the plug. Fix the leakage and I'll bet you will see an improvement. Rick.