1988 johnson 90hp v4

[stlrd85]

i think i have lower unit issues, but what exactly i don't know. i was cruisin' along at full throttle (didn't hit anything) and suddenly the motor is racing and the prop isn't spinning. there is no "click" when i put it in forward or reverse. any ideas?<br /><br />also, i've loosened everything that appears necessary to remove the lower unit, but it still won't come off...PLEASE HELP!!!<br /><br />

 

[Walker]

Re: 1988 johnson 90hp v4

I sounds to me like something let go. Clutch dog or maybe even your driveshaft broke.<br />Turn the prop by hand and see if the propshaft turns, although I've never seen a spun prop hub that wouldn't turn the prop at all. Before you take anything apart disconnect the shift cable at the motor and see if you can shift into gear by hand with the shift linkage.<br />Drain the grease from the lower unit and see if you get any metal pieces or large shavings.

 

[rodbolt]

Re: 1988 johnson 90hp v4

did ya remove the trim tab and then remove the 3/8ths bolt under it? there are 5 9/16ths headed bolts and one 5/8th hex bolt. and dont forgt to dissconnect the shift link. pull the hairpin clip on the stbd side by the lower carb and push the lever over. its easier if you remove the shift cable.

 

[stlrd85]

Re: 1988 johnson 90hp v4

you guys are QUICK!!! i guess to clarify, the prop turns by hand, but not by power. drained the oil and no shavings or metal--unless they're too big to come out.<br /><br />i'll look under that trim tab right now! dang, keys are gettin' all greasy here!

 

[stlrd85]

Re: 1988 johnson 90hp v4

took off the trim tab and took out the bolt underneath! it worked, but now i can see a long, thin rod that runs all the way up into the upper compartment. if i shift forward it pulls tight and if i shift reverse the gap gets wider. how on EARTH do i disconnect that thing to get this the rest of the way off? i'm one of those guys with WAY more time than money, so i gotta do whatever i can on my own. <br /><br />and thanks for all the help so far!

 

[stlrd85]

Re: 1988 johnson 90hp v4

now this is quickly becoming the most frustrating thing i've ever tried to do. i've taken off both cables (F & R) and taken out that hairpin clip. it (the rod) just won't come out. i'd tear out my hair if i had any!

 

[Walker]

Re: 1988 johnson 90hp v4

Okay, you need to take the tension off that rod. Its the shift rod. Put at least one bolt back in the lower unit and screw it in enought to raise the lower unit back up to the motor. Now push the linkage that you pulled the pin from in towards the middle of the engine. When the linkage releases from the shift rod.you will be able to rotate the linkage freely.

 

[stlrd85]

Re: 1988 johnson 90hp v4

got the shift rod out and it's all apart. the drive shaft? is sheared off at the bottom. now the problem is i can't get the sheared off section out. is this possible or am i SOL and need a new lower unit?<br /><br />and thanks again everyone!

 

[stlrd85]

Re: 1988 johnson 90hp v4

ok, here are the images of the damage. anyone know where i can get a used drive shaft for this motor? to recap, it's a 1988 johnson 90 hp 4 cylinder VRO.<br /><br />model: J90TLCCA<br />serial: R 7833373<br /><br />

<br /><br />

 

[stlrd85]

Re: 1988 johnson 90hp v4

ok, someone on another board said that i can take the driveshaft to a machine shop and have it welded and turned. will that work?

 

[sycamore]

Re: 1988 johnson 90hp v4

From your pictures, the weld will end up near the water pump keyway and seals. When you turn the shaft down you will be removing much of the weld strength and have mostly left what broke in the first place. If they do not get it straight (within a few thousand over the length) you will ruin bearings and seals. I'd say get a used, the labor to fix will be almost as much as a used and you would not have the quality.

 

[Joe Reeves]

Re: 1988 johnson 90hp v4

The driveshaft can be removed by gripping the broken top portion of it with a good pair of vice grips, and the pinion nut with the proper wrench.<br /><br />Look closely at the top broken portion of the driveshaft. On it you will see a part number such as 394614, 394615, whatever... a six digit number. What is it?

 

[stlrd85]

Re: 1988 johnson 90hp v4

so if i understand correctly, the part number is on the end that goes up into the power head? i looked all over and i just don't see one. is it up near the splines? as for the part in the lower unit, if the number is in there then i currently don't have all the tools to remove it. i don't have a pair of snap ring or retaining ring pliers. that's what i need to release near the prop shaft to get this out, right? i will have to get some of those pliers, but i don't want to if i'm going to have to take this in since i'll never use them for anything else.<br /><br />

<br /><br />regardless of part number, any idea how much a used one may cost? and the bearings still have to be pressed on by machine, correct?

 

[Walker]

Re: 1988 johnson 90hp v4

It will probably be cheaper to go with a used complete lower unit. It takes some special tools to get all the guts out of and back into yours if you do it yourself. If you have it done it will probably cost more than a used unit.

 

[stlrd85]

Re: 1988 johnson 90hp v4

Originally posted by Walker:<br /> It will probably be cheaper to go with a used complete lower unit. It takes some special tools to get all the guts out of and back into yours if you do it yourself. If you have it done it will probably cost more than a used unit.

any recommendations on where to find one?

 

[Walker]

Re: 1988 johnson 90hp v4

Ebay or ask around in your arae for a marine salvage company. I know there are some in Florida. Shipping cost is a consideration also.

 

[stlrd85]

Re: 1988 johnson 90hp v4

i think i found a few on ebay that are compatible. i'm waiting for the seller's to get back to me on that.<br /><br />a HUGE thank you to EVERYONE who helped me out here!!!!!<br /><br />

 

[Dhadley]

Re: 1988 johnson 90hp v4

What does he say it came off of?