Chrysler 85hp various problems

[slugsly]

My dad gave me his boat. It was abused pretty hard and I want to get it good shape. I'm really looking forward to not having to musky fish from my canoe this year

The boat is a Thundercraft ss1560 and the motor is a 1980 Chrysler 85hp. First problem is I think mice were using the foam that was inside the cowl for nests. I don't see any chew marks on any wires luckily but the foam was torn up and all over inside. I'm pretty sure my dad ran it with all this lose foam in there and I imagine some got pulled into the intake. I cleaned all up as good as I could. I cleaned the spark plugs, they were pretty fouled up. I charged the battery, got some new gas added oil and a can of seafoam. It wouldn't start. Sprayed a little starter fluid in the carbs and it started up but wouldn't keep running. Replaced the fuel line from the gas tank and after that it started right up. Took it to the lake and going slow in the no wake zone it smoked pretty badly. Got it going a little faster and it seemed to run well, didn't smoke. Going slow again it smoked pretty badly still. At higher speed it pulled hard to the right. Me and the battery were on the right side, friend was on the left side and I'm about 60 pounds heavier. switched sides and it still pulled to the right.

My questions are:

I'm confused on how to adjust the trim tab. Everything I read says if it pulls to the right adjust the trim tab to the right. But my understanding was that this meant swing the back of the tab to the right. The trim tab on this motor seems to adjust at the front? But I've never owned an outboard before. Currently the trim tab is all the way against the left edge. Added a picture.

Can I get a tach for this thing? I think it would be a good tool for answering my next question.

I have 2 props both of which have some pretty good dings in them and both say 15.25 19 on them. It's a small boat but these seem pretty aggressive. Should I get a different prop? Also, the dings are bad for balance?

I was thinking of 3/4 gallon or gas, 1 can of seafom, 3oz oil thing I've read about on here to clean it out some. Good idea?

After running the motor for a bit in the lake there was some oil coming out of the holes in the attached picture. Is this a weep hole for burnt oil or do I have a bad seal some place?

I really want to get this thing running well. I know I have a lot to learn and a lot to do probably.

 

[slugsly]

Re: Chrysler 85hp various problems

I think I was wrong about what the prop is, it has 524 19 stamped on it.

 

["B"]

Re: Chrysler 85hp various problems

Hi,

I'm new here too, so bear with me a bit. The trim tab/exhaust snout is set that way to counter the weight of pulling skier ofr tubes. you can try setting it at center and go from there. If you notice it is cast so that there is a little push to the right (facing the engine) thats is to compenste for normal engine torque. It's something you kind of have to play with to get it to your comfort level. As for the oily streaks, check the oil level in the lower unit, there are three screws in the right side of the case one says vent , one says fill and the one lowest on the case is the drain. Did you change the fluid in the unit? There are lots of lower unit questions and answers here so look around you'll find what you need. If you didn't change it maybe you should and make sure not to over fill it. Hopefully you'll be on the water trouble free.

 

[slugsly]

Re: Chrysler 85hp various problems

Thanks for the response.

I did change the lower unit grease. I moved the tab over some and the boat went straighter. Like you said I just need to mess with it to get it in the right spot.

I'm down to two main concerns. A motor that is reliable and reducing smoke at idle/low rpms. I started by checking compression, read approx 132, 128, 132 which should be good. Next I was going to clean the carbs and set that following the info in the sticky in this forum and borrow my friends timing light and check that.

What's the main cause of smoking at low RPMs? I've been told old 2 strokes just smoke a lot but I'm thinking I should be able to reduce it some.

 

[foodfisher]

Re: Chrysler 85hp various problems

Clean out the fuel recirculation system.

 

[jerryjerry05]

Re: Chrysler 85hp various problems

The tab or snout is where most of the exhaust exits.
It also controls the pull or steer.
If your boat pulls hard to the right turn it to the right.
The foam was a good idea untill after 20+ years the glue quit working.
The foam is crap too.
You REALLY need to remove the carbs and clean them.
The foam can cause a piston to burn up.Seen it and made a bunch of $$ fixing this.
It makes the motor a bit louder but you don't even notice after a while.
Like food says clean the recirc system.
Clean the carbs and make sure they go back right.
Top post is a thread from FrankA called a linc and sinc,do this.
I wouldn't mess with the timing.
These motors don't usually go un-adjusted unless you mess with them.
So please don't touch until you get a manual.
The gunk comming out is unburned oil/gas.
If it looks like new oil then a top seal or shift shaft seal might be leaking???
Change the oil make sure you DON"T touch the screw on the side of the lower unit.
It's the pivot pin for the shifter.
Can be a bugger to replace.
Guess that's enough for now.Gotta feed the dog.

 

[slugsly]

Re: Chrysler 85hp various problems

I got the fuel system cleaned up and it smoked a lot less but I think I have bigger problems. I have one of these http://enmco.thomasnet.com/item/enm-counting-instruments/tach-hour-meters-pt15-tachometer/pt15b2?plpver=1003&categid=100&prodid=3001156&origin=keyword which is set for 2 cycle engines. It seemed to read correctly at idle and lower RPMs. At WOT it was nearly 8k and my gps was reading 15mph. Does this mean the gears in my lower unit are messed up? Is this something that can be fixed or should I be looking for a replacement?

 

[emoney]

Re: Chrysler 85hp various problems

Could be a gauge problem. What does the motor sound like at WOT? Don't think ur motor is capable of 8K rpms?

 

[slugsly]

Re: Chrysler 85hp various problems

Could be a gauge problem. What does the motor sound like at WOT? Don't think ur motor is capable of 8K rpms?

It's loud. I've only heard it running as it is so I don't have anything to compare it to. Maybe the rpm gauge is wrong but I know the gps reading of a max of 15mph at wot is accurate and it's not a giant boat. The prop looks okay.

 

[jerryjerry05]

Re: Chrysler 85hp various problems

Sounds like a guage problem???
They would do 8000,not recomended.
If your running and the motor sounds like it's running fast and your only doing 15.
Then I'd guess the props hub has spun.
The gearing wouldn't make that much of a change.
Take the prop off on the inside mark the rubber hub with a marker or someway to tell if it slips.
Then go for a ride.See if it slips.
Looks are decieving!!!