help, its been in the basement for 20yrs

[tdoe]

recently got a 1969 rude 25hp. its got great compression and spark. just changed the plugs from champion j4c to champion rj8 as per the champion book said. 1st, does any1 know if thats right? seems odd going from a heat range of 4 to an 8? 2ndly, the carb was spotless when i took it off to clean it, but it wont fire up. when i prime the bulb it gets really hard and still wont fire. i removed the fuel line to the carb and the fuel shoots out under major pressure, does this mean my needle valve and or float is stuck or obstructed? just need to know if i'm heading in the right direction? thanx

 

[samo_ott]

Re: help, its been in the basement for 20yrs

That's an engine I have always wanted. A 22 cubic inch 25hp. Excellent power/weight ratio. If you have solid spark (as tested with a spark tester), try spraying some 50:1 premix fuel in the carb and see if it will sputter. If yes, the problem is fuel related. When you had the carb off did you change the needle? Did you put a carb kit in it? Did you set the float right? did you blow in it right side up and upside down to see if it was sealing ok?

 

[tdoe]

Re: help, its been in the basement for 20yrs

yes i blew the entire carb out gently w air then carb cleaner. the needle looked to be clean and moving freely. i did spray starting fluid into the carb and it does fire up, so i was assuming a fuel problem. i just dont understand why the fuel from the pump is staying under such high pressure? i suppose the float is stuck after all?

 

[mikesea]

Re: help, its been in the basement for 20yrs

After re reading your post ,these old eyes finally saw you had spark

 

[wilde1j]

Re: help, its been in the basement for 20yrs

This is what BRP recommends:

25HP 1969 - 1976 Champ J4C .030"

 

[F_R]

Re: help, its been in the basement for 20yrs

%$#@*%& Champion plug charts. They have marketing people, not certified mechanics. RJ8 is just plain ignorant and stupid!!! They figure if it fits the hole it will work.

J4C is the correct plug. Replaces the original J4J.

 

[bigmoe]

Re: help, its been in the basement for 20yrs

%$#@*%& Champion plug charts. They have marketing people, not certified mechanics. RJ8 is just plain ignorant and stupid!!! They figure if it fits the hole it will work.

J4C is the correct plug. Replaces the original J4J.

Is there a problem with the J8C? Would it cause any real problems?

 

[Glastrontizz]

Re: help, its been in the basement for 20yrs

Try spraying some fogging oil in the cylinders. That worked for me on a old rude that the PO couldn't get to start.

 

[wilde1j]

Re: help, its been in the basement for 20yrs

Is there a problem with the J8C? Would it cause any real problems?

Too hot; use the J4C as recommended.

 

[F_R]

Re: help, its been in the basement for 20yrs

Is there a problem with the J8C? Would it cause any real problems?

1. Too hot. Could cause pre-ignition and burned pistons. Especially in a high compression engine like the 25hp.

2. Too hot. Even if it runs ok, it will soon burn up the plug

3. "R" means "Resistor". Outboards hate resistor plugs. Makes them hard to start and misfires.

 

[bigmoe]

Re: help, its been in the basement for 20yrs

1. Too hot. Could cause pre-ignition and burned pistons. Especially in a high compression engine like the 25hp.

2. Too hot. Even if it runs ok, it will soon burn up the plug

3. "R" means "Resistor". Outboards hate resistor plugs. Makes them hard to start and misfires.

I was curious because my 65 18 hp has them in it. I guess I should change them.

 

[PS94]

Re: help, its been in the basement for 20yrs

Silly question, as I know nothing of carb-ed outboards, is the float bowl on correctly? I had a few old small engines that had a 'step' in the bowl, that, if rotated 90* from where they were supposed to be, wouldn't let the float drop, and starve the carb...

Is the needle jamming in the bore of the seat? are you getting fuel to the bowl, or is it full and not being venturi-ed into the air stream?

 

[outlaw241]

Re: help, its been in the basement for 20yrs

did you check compression with a gauge. im not sure if you under stood what sam otto meant by blowing in the carb, with the carb in your hand right side up blow in the fuel inlet with your mouth an you should hear air passing through the carb, turn carb upside down an blow again NO air should be passing through,with it right side up needle & seat should be open,with it upside down needle & seat should be closed. hope this helps

 

[tdoe]

Re: help, its been in the basement for 20yrs

man, all you guys ROCK!!!!!!!! thanks so much for all the input. i'm gona return those plugs and get the 4's tomorrow then remove the carb again and recheck the needle valve and float.