Time for a Rebuild?

[83ebbtide]

Hello all, new guy here.

Here is my problem. I have a 1983 175 Johnson on an 18' F/S. My engine has a hesitation/bog while excellerating out of the marina. If I chock it (push in the key) it will recover, get up on plane and run well. My first thought was fuel pump. Ran a compression test and found 95lbs on one side top to bottom and on the other 100lbs top 70 middle and 90 bottom. I know it needs a rebuild if not now soon. Should I address what appears to be a fuel issue or just start planning the rebuild? Guys where I live want $3500 on average for a rebuild on this motor. I am above average on mechanics and have rebuilt and repaired several automotive engines in my time. Is a rebuild on this particular motor something that can be done with a good manual or are there tricks to this that are best left to the pros? If I choose to rebuild it myself where is a good source for parts? Do I need to do a complete rebuild or can i just rering and bearing it assuming the cylinder walls are in decent shape. Basically I am looking for options on how to do this as economically as possible (not tring to be cheap). It is an old boat but still in decent shape and may be able to get 5 more years out of her.

Thanks for help and suggestions,

Jeff

 

[wilde1j]

Re: Time for a Rebuild?

You could probably do the rebuild with an OEM shop manual and some advice from those here.

Your immediate problem is a fuel delivery problem, which can have a number of causes, such as:
. air leak on pump suction side (bad clamp, cracked hose, cracked tank pickup tube, etc., etc.)
. malfunctioning anti-siphon valve
. plugged tank vent
. trash blocking tank pickup screen
. plugged fuel filter
. collapsed fuel line

You can confirm by using an alternate fuel source (portable tank) and see if problem goes away.

 

[Cofe]

Re: Time for a Rebuild?

Have you ever done a decarb on your motor?
If you haven't, it may free up your rings and give you better compression and help with performance.

 

[83ebbtide]

Re: Time for a Rebuild?

No decarb has been done as of yet. Talking to some local guys they feel it needs a rebuild. Would the low compression on one cylinder (70lbs) cause that drastic of a performance drop as I am being led to believe by some local repair shops?

If it was your boat what would you guys do?

 

[Al-53]

Re: Time for a Rebuild?

do a de carb first see if your compression comes up..you may have a stuck ring is all...take plugs out and spray sea foam in plug holes let sit over nite......then mix up 1 gallon of fuel with 10 oz of sea foam in it run it with that mix..it will smoke like hell...and clean the carbon out..then take another compression test..see if you levels come up...

then go from there

Al

 

[nymack66]

Re: Time for a Rebuild?

Buy a rebuild kit plenty of dealers on Ebay under 900, get a OEM manual it is fun you can do it. If you run a old motor one needs to know how to fix it. If not have the check book ready !!! or keep this motor for spare and snag a good running motor you can check craigs or ebay ...Plenty of options you have to decide ..

 

[83ebbtide]

Re: Time for a Rebuild?

Just found out my brother has been running a 40:1 mix when he has used the boat so I believe the decarb is certainly in order. So here is my plan. First try to found and correct any fuel problem. Second, run the decarb procedure and recheck the compression. If these fail to correct the problem search for a rebuild kit, get a good manual (Seloc?) and begin the rebuild. Will any machine work be required or will this be determined by inspecting the cylinders and crank? How successful has the decarb been on bringing up the compression or freeing stuck rings?

If the decarb works I owe you guys lunch!

 

[jonesg]

Re: Time for a Rebuild?

A good decarb can put the compression right where it needs to be.
Mine came up from 70psi to 83psi after mutiple soaks with seafoam directly on the rings. It dissolves carbon will not damage alum.
We also sprayed some in the carbs while running on a hose.
Lots of guunk came out.

You couldn't rebuld a lawn mower with seloc manuals.
Get the real factory service book.
www.outboardbooks.com
Have your model number handy for ordering.

I think you're getting way too far ahead of yourself speculating what it might cost, but doing it yerself with the manual and help here, have a machine shop fit the piston should be under $700.
Or if you decide to do the whole lot, order a rebuild kit for $1000.
http://www.powerheadkit.com/johnson.htm
Might cost $120 per cyl for the machine shop.
Still way cheap and you learn a lot.

 

[wilde1j]

Re: Time for a Rebuild?

No decarb has been done as of yet. Talking to some local guys they feel it needs a rebuild. Would the low compression on one cylinder (70lbs) cause that drastic of a performance drop as I am being led to believe by some local repair shops?



If it was your boat what would you guys do?

NO! to performance drop.

DECARB, as has been suggested.!

 

[83ebbtide]

Re: Time for a Rebuild?

Thanks for all the advise. I will be trying the decarb SOON and will let you guys know the results.

If anyone has anymore suggestions please chime in. I'd rather have too much info in this case. Don't want to miss something.

 

[wilde1j]

Re: Time for a Rebuild?

Seloc and all the other third party manuals aren't held in high regard here. Get yourself an OEM manual.

 

[nymack66]

Re: Time for a Rebuild?

If you are going to go the re-build route I can personally recommend http://www.powerheadkit.com/johnson.htm since I did purchased and done business with them in the past, ask for Vaun he is awesome to work with tell him Andrew from Orlando recommended his business to you, he is never tired of my phone questions or when I need something done one year after my purchase. Hopefully the de-carb works.
(813) 673-8866

 

[Cofe]

Re: Time for a Rebuild?

A good decarb can put the compression right where it needs to be.
Mine came up from 70psi to 83psi after mutiple soaks with seafoam directly on the rings. It dissolves carbon will not damage alum.
We also sprayed some in the carbs while running on a hose.
Lots of guunk came out.

You couldn't rebuld a lawn mower with seloc manuals.
Get the real factory service book.
www.outboardbooks.com
Have your model number handy for ordering.

I think you're getting way too far ahead of yourself speculating what it might cost, but doing it yerself with the manual and help here, have a machine shop fit the piston should be under $700.
Or if you decide to do the whole lot, order a rebuild kit for $1000.
http://www.powerheadkit.com/johnson.htm
Might cost $120 per cyl for the machine shop.
Still way cheap and you learn a lot.

Very well put Jonesq
I was just wondering about the multiple soaks with seafoam directly on the rings? How is that done? What is you're procedure?

Wild1j has some good points on fuel problems.....

OMC is the only way to go for a good manual. It is good to have even if you don't plan on a total overhaul. "See ebay"

1983 is a long while for rubber to exist without break down. So I would also suggest replacing fuel hoses with ethanol safe rubber. "Grain alcohol and old rubber get you in trouble."



By the way I like steak.

 

[ezmobee]

Re: Time for a Rebuild?

Ok guys let's help him out with a manual. I'm sure they didn't change these motors every year. I found these on ebay. Which one would be the same as his '83. My guess would be the first one I listed below would be the same. Any major changes from '81 - '83?

1981
http://cgi.ebay.com/ebaymotors/1981...Motors_Manuals_Literature&hash=item2eaba58ca3

1980
http://cgi.ebay.com/ebaymotors/John...Motors_Manuals_Literature&hash=item4837f91611

1978
http://cgi.ebay.com/ebaymotors/John...Motors_Manuals_Literature&hash=item4837f91611

1987
http://cgi.ebay.com/ebaymotors/1987...Motors_Manuals_Literature&hash=item2eae3c2297

 

[wilde1j]

Re: Time for a Rebuild?

I would get one for the right year. If 'almost and sort of' are OK, then get Seloc, which is a POS in my opinion.

 

[Cofe]

Re: Time for a Rebuild?

No, No not Seloc........try ken Cook at http://www.outboardbooks.com/ only if you don't want to wait on something to "appear" on ebay for a good price.

 

[83ebbtide]

Re: Time for a Rebuild?

Very good info! I will get an OEM manual before attempting any rebuild. Hopefully I'll get lucky and won't have to do that just yet though. I'll address the fuel issue first. Hoses were all replaced about 5yrs ago. Carbs could use a rebuild I'm sure since it hasn't been done in the 10yrs I've owned the boat.
Then on to the decarb.

If I get to the rebuild I will tell Vaun that Andrew from Orlando said to call.

Jonesq, how did you soak the rings multiple times? I am VERY interested in your procedure as well.

Can't thank you guys enough. Now I just need to make time to work on it.

 

[boobie]

Re: Time for a Rebuild?

Get the Ken Cook manual!! Seloc, Clymer and the rest of them are good to set your coffee cup or beer can on while working in your shop. They also make great knee pads if needed. Sounds to me like first you need a good de-carb and then some carb work if as you say, "you push the choke in and then it will take off".

 

[83ebbtide]

Re: Time for a Rebuild?

Pulled the plugs and sprayed some Seafoam into the cylinders to let it sit for a good 24 hours. Then will fire tomorrow afternoon and mix some with the fuel and spray some directly into the carbs. Check the compression afterwards and hopefully do just a carb rebuild if the rest of the fuel system checks out first.

 

[83ebbtide]

Re: Time for a Rebuild?

Ok, I did the decarb once as described and the compression came up about
5lbs so I'm still outside of spec. According to my brother it ran a little better once warmed up but I think we were still burning off some Seafoam in the fuel bowls and lines. Eventually it got to where I could pop it right out of the hole.

I am still doing the carb rebuild which is currently underway. Never been done since I have owned the boat (10 yrs). Waiting for the other two kits to get here to complete this.

I still have a pop out the exhaust (prop hub) which I can't figure out, there is no pattern to it just does it randomly. I put my timing light on each cylinder and it seemed to be firing well. This was done on the muffs at my house. Pulled the plugs back out to inspect and all were brown and wet. I have noticed fuel underneath my carbs so will check the hoses for cracks and leaks when I install the carbs. I notices a larger hose going to the primer solenoid that I could easily pull off so will correct that as well. Could that be the cause of the bog and pop I have been having?

You guys have been a lot of help!