Chrysler 15 hp won't start - backfires

koz

Cadet
Joined
May 26, 2004
Messages
7
Oh Ye Guru's of the Outboard.. Can you point me in the right direction. I have a 15 hp Chrysler<br />model #152H2H.(1984 I think) Last year the engine overheated while out fishing. I rowed the boat back to the landing and brought it home for the year. I replaced the impeller thinking that it might need replacing seeing it was the original. I cannot get the darn thing to start. I replaced the plugs ( they have spark ) but all I get is a loud back fire about every 15 pulls on the starter rope. No fuel line blockages. I am fairly good with a wrench, but before I order a repair manual and start tearing the darn thing apart, I was wondering if there might be something "easy" to fix or check first. I do not want to end up spending a lot of time and money on parts, but I don't have an extra $1500 laying around to buy a new motor. Any sufgeestions would be greatly appreciated. I did read the other post in this forum on another 15hp chrysler. <br /><br />Thanks,<br />Koz
 

eurolarva

Rear Admiral
Joined
Jun 24, 2003
Messages
4,182
Re: Chrysler 15 hp won't start - backfires

Back fire is telling me timing is off. Is it backfiring through the carburator or the exhaust? Easy thing to check first is to see if you accidently crossed the plug wires. The next thing I would wonder is if you somehow broke the flywheel key and now the timing is off.
 

koz

Cadet
Joined
May 26, 2004
Messages
7
Re: Chrysler 15 hp won't start - backfires

Eurolarva:<br />I think you are on to it. It backfires through the exhaust. The Plug wires are in correct order.(the top plug wire is labeled "top" and is in the right place.) I got the flywheel of and the key is fine. How do you set the timing on this motor?<br />Magnetron ignition. Doesn't look like there is anything to set.<br /><br /><br />Koz
 

koz

Cadet
Joined
May 26, 2004
Messages
7
Re: Chrysler 15 hp won't start - backfires

From bad to worse. I removed the flywheel, checked connections, and cleaned off contacts.<br />The key is fine. I reinstalled the flywheel, and now I have no, or very little spark. I am tempted to buy a tune up kit ( condensers and contacts) but what if this is not the problem? Any suggestions, or should I start looking for a new motor?<br /><br />Koz
 

eurolarva

Rear Admiral
Joined
Jun 24, 2003
Messages
4,182
Re: Chrysler 15 hp won't start - backfires

I would go buy a compression tester. They cost about 30 bucks at sears or you can probably get one from an auto parts store. You are suppose to test compression on a warm motor but I would try it on cold just to see what you get. If the overheating caused problems with the power head it is a coin toss as to wheather you want to fix it. A new 15 HP is around $2000. Your motor is a 1982 and here is a link for parts Chrysler 15 HP <br /><br />My manual says these could be the problem on backfire through exhaust<br />Cracked spark plug insulator<br />Carbon path in distributer cap (yours probably dont have a distributer)<br />improper timing<br />Crossed spark plug wires<br />Good Luck
 

koz

Cadet
Joined
May 26, 2004
Messages
7
Re: Chrysler 15 hp won't start - backfires

Thanks euro -dude!<br /><br />My gut instinct is telling me to go look for a new used motor! Lets see.....<br />I put in new plugs - No cracks in the insulator.<br />No distributor cap - Magnetron instead<br />Timing - as far as I know - no way to set timing<br />Key in good shap and in place,<br />Plugwires crossed - Nope. the wires are clearly labeled and in the right place.<br />Powerhead - with my luck -probably warped.<br />Heads of tails.... ???<br />Thanks for all the help.<br /><br />Koz
 

fixin

Senior Chief Petty Officer
Joined
Apr 23, 2004
Messages
775
Re: Chrysler 15 hp won't start - backfires

Just a thought:did you try a really big hammer and few joice words???I have an old 56 johnson,only thing that works on it :p just playing,did you check the plug wires with a ohm meter?that oll johnson gave me a fit one time over a bad plug wire.
 

rbruce63

Petty Officer 1st Class
Joined
Aug 30, 2003
Messages
212
Re: Chrysler 15 hp won't start - backfires

Koz:<br /><br />Before you find a used motor and spend $750 take the head apart and replace the head gasket, resurface the head as all aluminum head will warp, do this in a flat surface and in an eight patern. Retorque using a correct torque meter from the center screws to the perifery. You will probably spend $150 doing the following jobs: <br /><br />Do replace the impeller and make absolutely sure that the water pump is sealing properly with the base of the lower unit, finally, make sure that the grommet that seals the water pump with the water inlet pipe.<br /><br />Was the gasoline drained from the carburetor? Did you use gasoline conditioner/stabilizer? If not you probably have gummed up the carburetor and this will need care.<br /><br />Finally if all this fails, please don't throw the motor to the garbage and fina a reputable Chrysler mechanic to fix it.
 

koz

Cadet
Joined
May 26, 2004
Messages
7
Re: Chrysler 15 hp won't start - backfires

fixin and rbruce63:<br /><br />I like the hammer idea.<br />I cleaned the carburator.<br />I will check plug wire with ohmeter.<br />I have allready replaced the impeller.<br />Reputable Chrysler mechanic? I guess all I got around here is a bunch of mechanics who keep telling me the same thing - " Can't get parts for chrysler outboards no more"<br />I guess they never heard of the internet!<br /><br />Eurolarva - What do you think? Should I pull the head, sand it down, replace the head gasket, replace plug wires, contacts, and condensers?<br /><br />What if it doesn't go then?<br /><br />Thanks for the ideas guys!<br /><br />Koz
 

eurolarva

Rear Admiral
Joined
Jun 24, 2003
Messages
4,182
Re: Chrysler 15 hp won't start - backfires

Have you tested compression yet?<br /><br />The back firing is what gets me. I want to think timing inspite of the fact that it overheated. Another option is to get another motor. Then work on this motor as a hobby. If you get it fixed you can sell it or the other motor. That way you are back on the lake fishing. That is the most important part is getting back on the lake. <br /><br />I have overheated my chrysler twice now where it just siezed up and shut down. After cooling down It has always started back up.
 

koz

Cadet
Joined
May 26, 2004
Messages
7
Re: Chrysler 15 hp won't start - backfires

Eurolarva:<br /><br />I haven't checked the compression yet. I too have overheated my engine ( the local lake I fish is full of millfoil) and after it cooled down, and I removed the weeds from the intake, it ran just fine. I am doing exactly what you suggested. I am in the process of finding a new used motor ( which is very hard to find in 10,15 or 20 hp ) and I will tinker with the one I got. If I get it running I can sell it. I have a old Evenrude 5hp to use untill I can find another motor. It's not very fast, but it beats the heck out of rowing, or worse yet, not fishing! The link you gave me for parts is great. Do you know how a person can check the strator?<br />Koz
 
Top