Chrysler 105 hp prop question

[jmk]

I just got a chrysler 105 outboard motor. It came without a prop. Does anyone know what the diameter and pitch is standerd for this motor? Mine has the exhaust out the middle. I see they sell three different sizes here. I'm not sure what one to get. I will be useing the motor for fishing, and not pulling skiers. Thanks, jmk.

 

[Frank Acampora]

Re: Chrysler 105 hp prop question

I need to know if it is a one piece or two piece lower unit. Need to know the year of the engine. THEN, I need to know what size boat it is on. A photo would help.

All Chrysler engines used a 13 inch nominal diameter prop. Pitch varied with size hull and load.

 

[jmk]

Re: Chrysler 105 hp prop question

Thanks, I have a 19' alluminum lonestare. It's a deep v about 1,200 lbs.

 

[jmk]

Re: Chrysler 105 hp prop question

Lonestar, Palara 77 105 chrysler one piece. The boat is probably even heavier with added weight.

 

[Frank Acampora]

Re: Chrysler 105 hp prop question

The 105 Chrysler was later down=rated to 90 but it is still a good workhorse engine. The one piece lower unit is a much better design than the two piece AND you still have a selection of props from small gear case Mercury engines, or Force engines.

A 19 foot aluminum boat is lighter than a comparable fiberglass one. BUT: Without knowing current performance, the correct prop is just a guess.

You want to keep that engine in the 4500-5500 RPM range at wide open throttle and it is happier if you prop it for 5000-5500.

First GUESS would be a 13 X 17 pitch prop. Buy a used one at the auction if possible. Then, if you have a tachometer, see what the RPM is and go from there.

 

[jestor68]

Re: Chrysler 105 hp prop question

The Michigan Wheel web site only shows 15 and 17 pitches available for the 105(1977-1978).

Then you click on "where to buy" and it shows a list of on line suppliers. Iboats is out of them according to the prop section.

I noticed a supplier had 15,17,and 19 pitches listed.

Or you can just Google "Chrysler outboard props" to find suppliers. It appears that Michigan is the only one that still makes them.

 

[jmk]

Re: Chrysler 105 hp prop question

Thanks guys, I will check into them. I just did a compression test and the top is 90, then going down in order from there I have 125, 125, and then 70. Thats scary! I new I should have checked it before buying, but I only paid $200 for it and he said it ran fine. I would just need to do the usual to it. It sat for years in a pole barn. I pulled the head off and it wasn't even stuck to the gasket on the head side. There is real mid rust in the cylinders more so at the top of the strokes. I can wiggle the pistons a bit, not sure if thats a good sign? I sprayed copper spray on the the gasket after wiping out the cylinders with motor oil, and cleaning everything back up. I bolted it back up and I got five more pounds on each cylinder. I wonder if I run it for a while if I can get it going if the compression will come up, or do you think I have a parts motor? I also wonder if I should have just put a new gasket in it. I just kinda wanted to see good readings before putting any money into it. I was planing on cleaning the carbs out and seeing if it will run. checking that the pump is pumpping water too. What do you think? Is it possible that from sitting and rusting a bit that it will loose compression like that and be able to overcome it? I really don't feel like breaking it all the way down.

 

[jmk]

Re: Chrysler 105 hp prop question

 

[jmk]

Re: Chrysler 105 hp prop question

well I guess those wont help much. There realy isn't any lip at the top of the cylinders just rust. Maybe I should take the head back off and spray some PB Blaster in there. I have some pit corosion where the metal paryt of the gasket seats. I also have a couple of gauges or dents that the gasket might not be sealing up.

 

[jmk]

Re: Chrysler 105 hp prop question

 

[jmk]

Re: Chrysler 105 hp prop question

 

[jmk]

Re: Chrysler 105 hp prop question

View attachment 186828View attachment 186829

There thats what the cylinders looked like before I wiped them out with a rag. There was still some rust but most came out. After cleaning the gasket area in the double cylinder picture you can see a dent on the top left side. Is there a way to fill that? I was thinking of maybe trying to use copper spray as a scratch filler and sanding over it. I turned the motor over with all the plugs out for a bit and then checked the bottom cylinder. It came up to 90 now. It was at 70, and the top one is at 100. I'm hoping that they will keep on coming up. I started to take the carbs off to clean them. I will have to read more on how to disconect the choke. My other motors had a clip there. There is some tar in the bowl. I will have to take the pump off too. The hoses are hard. I had to cut it off. I might have been able to have heated it a bit, but I figure might just as well replace the hoses. I didn't recheck the middle two seeing that they were good before. Hopfuly they will get better once I get it running. I have to make a switch board. I am just jumping the starter right now to turn it over. I will need to get the ignition hot with a switch, and it would be nice to have a switch to give the starter silenoid power instead of pressing the jumper cable.

 

[steelespike]

Re: Chrysler 105 hp prop question

You might try a decarb treatment with something like Sea Foam.
It may help free up any carbon built up in the rings.
I'm no Chrysler expert but keep in mind that the ignition can be damaged by careless trouble shooting.
I also believe some motors have a magneto type ignition and others an automotive type.
I'm sure Frank knows better than I if and what of this info applies to your motor.

 

[jmk]

Re: Chrysler 105 hp prop question

The book says to ground out the ignition so it is disabled and cant start a fire. I didn't ground it out because I don't have gas in it. It has a distributer run by a belt with a capacitor charged coil. I didn't think I was hurting it. Maybe I should read up on the grounding out part. I hope I didn't hut the cdi system. Thanks for the heads up. I have been reading about the decarb. I read that the best stuff to use is mystery oil. I read to fill up the cylinder with it and let it soak. This is why I was wondering if I should spry pb blaster in there. That seems like it would penitrate good. I am willing to try everything before taking it all apart and rebuilding it. I wonder if there is a taper to the cylinders and while the motor sat for years the rings got stuck at different parts of the cylinders. I cleaned the carbs today and bought new fuel line. I took the motorcycle for the first ride this year here in Michigan it was a nice day to ride it to get the fuel line. I used all the old gaskets because they were still in one piece and I don't want to put money into it til I know she will run right. This motor has a stator cdi coil and distributer. Do you think I hurt it?

 

[jmk]

Re: Chrysler 105 hp prop question

Here is the electrical system.

 

[jmk]

Re: Chrysler 105 hp prop question

I tilted the motor back and sprayed a bunch of pb blaster into the cylinders. I move the pistons up and down a bit back and forth every now and then. I will let it soak for a while.

 

[jmk]

Re: Chrysler 105 hp prop question

Well, with the weather being cold I havent worked on the motor much. I did find out that the wrong plugs for the motor were in it. They had the plugs without the grounding strap inside. The books call for a ground strap plug. I ordered those and should be in today. The motor has been tilted back. I did that manualy. It was hard fighting the power trim to get it to the locking possition. I couldn't get it to go back down manualy so I figured out how to run it by switching the power back and forth on the power wires with the ground wire grounded to the battery. After lowering it I ran the motor over with out plugs and blew out the pb blaster. It parcialy leaked out the lower carb in the up possition and out the exhaust. Not much came out of the plug holes after soaking for a week. Anyway, I checked the compression and now I have 122, 130, 130, and 100 on the bottom cylinder. I think it will run like that and I can do a decarb with some sea foam. After reading up on sea foam I found out that deep creep sea foam is the same as the other sea foam in the can with the screw on lid to dump into fuel. The only difference is the name and one is in a spray can. I have a can I will use once it's running and I think the motor will be fine. Then I will get the time compliance parts that should be changed. I was surprised how little torque the head bolts get torqued to. My wrench doesn't even read that low. 20 foot pounds is the lowest setting. I think the inch pound setting converted to 14 foot pounds. I just backed it off below the 20 lb seting to about where 14 would be. That gasket seems to be working. I will find out more once water runs threw the power head. I will order the water pump now. I think the compression readings will get better with it running, and after decarbing.

 

[Frank Acampora]

Re: Chrysler 105 hp prop question

Cylinder head bolt torque is 225 INCH pounds. I don't like using foot pounds, it is not as accurate, but if you must, this works out to 18 FOOT pounds. You torque in a spiral pattern from the center two bolts. Do it in three steps--like 150, 200, then final at 225. Better to buy an inch pound torque wrench from Sears.

With a new head gasket, after running the engine for about 1/2 hour or so, or at the end of the day, re torque the head bolts.

I don't know what you mean by a grounding strap inside the plug. Correct plugs are surface gap, Champion L20V or UL18V, NGK BUHW or BUHX. You can even get away with the Mercury L76V plug.

It will run with the compression numbers you have, but it really would be better with 130 on all cylinders. Once it gets some running time, the low cylinder MAY come up some but I doubt it. You should think about eventually rebuilding it as a winter project. It is relatively easy and cheap.

Since this is the prop forum and we have sort-of hijacked this thread, you would do better to go to the Chrysler/Force forum for further discussion. I don't know how to transfer threads so perhaps the moderators will do so.

 

[jmk]

Re: Chrysler 105 hp prop question

I moved over to the Chrysler outboard forum.