60 hp johnson rebuild

[scotgoplen]

i have a 1990 60 hp johnson,it has 90,90,75 lbs compression its a 3 cylinder of course.it wont hardly idle i cant troll with it,no low speed take off,i have to open it up slow or it will kill.but at wide open it runs fine.the dealer says i need a rebuild,is he right?the vro has been changed and he unhooked the oil i now mix it.if it wasnt for the lack of low speed idle id leave it alone .is it easy to buy a rebuilt head and change it?what kinda money should i expect to spend to fix this

 

[OBJ]

Re: 60 hp johnson rebuild

Welcome to iboats scotgolplen!<br /><br />I think the first thing I'd do is pull the head and have a gander at the holes. If scoring is present, yep....rebuild. The VRO probably wasn't the cause of your malady. Sounds more lean running on the low cylinder.<br /><br />For the most part, if you get an OEM service manual and parts manual, you could do the rebuild yourself if you have any mechanical ability at all. You would most certaninly also include the carbs in the plan as well as new fuel lines, pump impeller, t-stat.<br /><br />Total cost would depend on all you replace. If you just punch out the bad hole and install an oversize pistion, hone the rest if in specs, this would help over all cost. Being a 90' year, I'd think about replaceing bearings also.<br /><br />First thing to do is check the engine holes and see what's up. Then get a manual if you plan to do it yourself.

 

[reeldutch]

Re: 60 hp johnson rebuild

if those compression numbers are correct then i would do what obj suggested and pull the head off.<br />may be youl be lucky and a good decarb will bring your compression back.<br />i thougt the numbers on a 60hp should be at least over a 100 psi and only 15 pounds differ between the higest and lowest numbers.<br />so pull the head and post back what you find.<br />and we have to figger out what caused aal your trouble.<br /><br />reeldutch

 

[DHPMARINE]

Re: 60 hp johnson rebuild

Just a thought... when I see numbers like that I retest #1.If it is down from 90psi,the first reading,you may have a battery problem.<br /><br />DHP

 

[Solittle]

Re: 60 hp johnson rebuild

Also do a thorough decarb and retest the compression befor you start grabbing wrenches.

 

[scotgoplen]

Re: 60 hp johnson rebuild

thanks,whats a decarb?ive rebuilt afew car engines but never had a 2 stroke apart, i had all 3 carbs rebuilt and a new thermostat put in.also my tach and voltmeter and trim quit about the same time,where would i look to check out these?they worked before, tks

 

[Solittle]

Re: 60 hp johnson rebuild

Go to the red search at the top of the page & enter "decarb" as a search arguement. Decarb stands for removing the carbon in the cylinder and especially the rings. When the rings get stuck they do not seal properly and then -----low compression.

 

[scotgoplen]

Re: 60 hp johnson rebuild

whats the procedure for that? i saw one guy witha can called powertune i believe,he was spraying it in the carbsand then kinda covering it with a rag ,maybe he tried it on my motor already? i dont know anything about 2 strokes at all. what ratio are they suppose to run at? 50-1 ? tks

 

[Solittle]

Re: 60 hp johnson rebuild

Read & learn - - Go to the red search at the top of the page & enter "decarb" as a search arguement. Decarb stands for removing the carbon in the cylinder and especially the rings. When the rings get stuck they do not seal properly and then -----low compression.