Logo

Cost of rebuild 98 Johnson 90hp

gone_postal

Regular Contributor
"I have another thread on here

"I have another thread on here regarding my engine's compression and have had some good advice. From the back of the motor, top left 100, all others 120. I was hoping that it would only need a simple decarb, but after my third shot and taking it out twice fishing & cruising and consequently burning about 10 gallons of SeaFoamed gas through it, things appear to be getting worse. After my first decarb, the cylinder hit 105 - today was only 90!!!! Other three are still showing as 120, so I doubt my gauge is wacky. It idles like it has a lopey cam, but sounds great when cruising, wot, etc.

A lady at work's son is a marine mechanic - seems trustworthy. I called him today and just over the phone he is recommended a rebuild. He would obviously do a visual inspection first, but said rebuilding one cylinder is just a patch and that the labor between 1 and 4 isn't that much different b/c it's a complete teardown to hone that one cylinder anyway. He also won't do a rebuild without replacing gaskets, servicing lower unit, water pump, etc b/c he said he doesn't want something else to break and risk his reputation on the job. Seems reasonable. Anyway, he was guestimating $1500-1600 for one cylinder or around $2000-2100 for all depending on block condition - whether they would just need new rings, etc.

Sounds like I'd have a "new" motor, but not sure what that's good for. What is the life expectancy? Could I expect another 11yrs or just 2-3? He said that mine in its current condition could last a week or a year or two - who knows, but that one thing is for sure - I have a cylinder issue and it will get worse and possibly take the block out w/ it.

I guess my only other option is a new 4 stroke - would LOVE that, but I don't want a payment on a $10,000 motor, so it looks like this is my only real option. Is it a reasonable price?"
 
"do the complete rebuild ,it s

"do the complete rebuild ,it sounds as this guy knows his stuff,thats right about everything gaskets water pump thermos etc...
do the tear down before serious damage happens!
it will be like a new engine and will last for years/years""""""""
that sounds like a good price too.i did my 90 for around 1200.
i did the work. and it runs great.
thumbs_up.gif







'"
 
Rebuild it and be thankful you

Rebuild it and be thankful you caught the problem before you didn't have that option. I would stop running it and get it done before it does let go. It happens in under a second and then its too late.
 
"The price sounds quite good -

"The price sounds quite good - $2500 is about average.

And yes, you would have a "like new" motor. He sounds like he is a decent tech - I too agree, best to do all cylinders while you are in there.

A rebuilt 90, properly maintained can easily see another 20 year plus of service.

Personally, I would suspect that this rebuild is more the result of a fuel issue (lack of oil to number 1 cylinder) than any actual defect in the powerhead itself. I would have the carbs rebuilt as well - a couple hundred extra bucks is very cheap insurance.

As you point out, the price of a new motor is staggering..."
 
"He said he would clean the ca

"He said he would clean the carbs - not necessarily a "rebuild", but hopefully they don't need it. I hope to drop the boat off tomorrow and he said it'd be a few days before he could actually get to it for inspection b/c he's quite busy right now. $2k was just a ballpark - I'm sure it'll be a little more, but as I'm trying to tell my wife, it's well worth it and cheap insurance when you compare it to a new motor.

As a random thought, is there anything that can be done during the rebuild to up the hp? It'll obviously be bored out a little, but shaving the head, different pistons, etc exist for more compression or any other way to increase hp? The boat is rated for a 115, so I figure 100, 105, etc would be pretty sweet if a 90 can bump to that. I'd be willing to run 89 or 93. It's just a thought - I'm a little curious."
 
"bored or not dont push it,you

"bored or not dont push it,your not going to get that much more out of it,in the long run it will only cost you more to run it(fuel)
i think you will notice a big diff when its done
nothing beats a good reliable engine."
 
"Andrew, even if you could eas

"Andrew, even if you could easily increase your current 90 horses to 115, under perfect conditions it would only give you about 3 more mph at the very top end - and as Charles notes, cost you more gas.

Unless you add a cylinder or 3 and significantly increase the displacement (by greater than 50%) you will not notice much improvement. The bottom end torque would be the same and all the way up through the power band until the last half inch of throttle would be the same as you currently have.

Plus you would only be adding internal stress to the motor which would shorten it's lifespan.

Enjoy your "like new" 90 when you get it back and keep a few extra bucks in you wallet to spend on gas so you can get out and enjoy the boat..."
 
10 4. I appreciate the input e

10 4. I appreciate the input everyone. I'm going to try and get it in to him today and I will update the thread or create another w/ the progress or if there are any other questions. Thanks!!
 
"Well, thought I'd post an

"Well, thought I'd post an update in case anyone is still following this.

The guy finally tore into it yesterday. He said the motor has definitely overheated at some point in time b/c the cylinder o-rings were dry & cracking. Cylinder 1 had water in it and all cylinders showed signs of scraping / wear. Luckily he said it's not major enough to require boring out and that a simple hone will be fine. He's recommended a full rebuild which will consist of basically brand new everything except the crank, block & rods. All bolts, bearings, gaskets, rings, water pump, etc will be new. The carbs will be rebuilt and we will also scrap the VRO system (he requires it or all new lines & pump otherwise no warranty). He will warranty it for a year and the price was quoted $2400. I'm hoping that cash may lower that a few hundred, but we'll see.

I'm excited about having a "fresh start", but my wife sure isn't - the boat isn't even registered yet!!! Luckily I feel I got a good enough deal on it to justify the rebuild and hopefully it'll give me 10 or more years of reliable service.

I am curious though, since I will have a "new" powerhead, how reliable are the bottom ends? I've never really heard of anyone having issues, but I guess like anything, with time it's bound to happen."
 
just keep a good eye on the ge

just keep a good eye on the gear case oil/look for any water.a seal job wont cost much if needed.
 
"Alright, thanks.

I got to


"Alright, thanks.

I got to go see the motor today - pretty darn cool seeing it all apart. He has started cleaning things up - heads were sanded/polished smooth already. The parts will be in Tues, block done Wed & he'll be in the water w/ it Thurs breaking it in - Fri at the latest. So, that means I get to go fishing next weekend!!! (which, if Weather channel's 10 day forecast is correct, will be crappy weather....mid 70s and sunny all week and mid 60s & raining for Sat & Sun....gosh I hope they're wrong)."
 
"---2500...in s central texas.

"---2500...in s central texas..is unheard of for that eng,..unless,they reuse all old parts...i,prefer my customers,spend thier money,on new parts,rather than labor.....
that said,..i do not,and have never in 32 yrs,done ..'short' overhauls...."
 
If you have no real previous h

If you have no real previous history with this mechanic I would request that you be given a chance to see the engine before the heads go back on the block. Just to be sure you are getting all the new parts you think you are getting. I only fully trust mechanics I know personally and not all of them! lol If fishermen can lie..so can mechanics.
 
"Well, although this is my fir

"Well, although this is my first experience w/ this mechanic, I work w/ his mom & I know their family has been in the boating industry for almost their whole lives (as a side job, she is a broker for Hunter sailboats).

I have been to his shop 3 times since I dropped it off last Friday and have seen the progress and he has an open door policy and said drop by anytime, bring my camera, etc if I want photos for a scrapbook or to prove the work was done if I ever decide to sell it. Anyway, I fully trust him - have a receipt for the parts ordered and it has a 1yr warranty, so that installs confidence. I do know he is giving me a break on labor b/c he's only charging what it's actually taking him and not the 21 or 24 hrs of "book value". I do appreciate all of the input & concern and it is helping to reassure me that at least I'm not getting screwed (and probably actually getting a good deal)."
 
Back
Top