Chrysler 20hp off and on water coming from indicator

[Chryslerman123]

So, finally got my 1971 chrysler 20hp outboard running. Ran it in a 55 gallon barrel. When I first start it, water sprays out indicator perfectly when idling. Once i give it a little throttle and go back to idle, there is very, very little water coming out of the indicator.it looks like no water is coming out at all sometimes. I have never ran it for more than two minutes at a time because I'm scared it's not getting enough water. If you let it set for a while and then start it up, it is the same thing every time. The impeller has been sitting in it unused for 25-30 years but was new at the time. It is fairly flexible with no cracks or anything. The only thing is that it has taken a "set". I pulled the lower unit after running it and checked the impeller and it is in the same condition it was before I ran it- seems like nothing is wrong with it, or, is there another problem?

 

[Nordin]

If you mean with "it has taken a set" that the vanes are bended and still has that position even if you pull the impeller out of the housing...........then that is the issue.

The vanes should be flexible and should flex in and out depending on have high the RPM is.
It will flex in if the RPMs increase and out if it decrease.

 

[jerryjerry05]

The impeller needs to be changed!!!!
You could try flipping it over while you wait for the new one.
​If it pumps then?? you still need to change it.

Is this a salt water motor?
Did it get used in shallow water a lot?

These pics are from a running motor.
A HOT running motor.

​2 things I do to any motor I work on: 1 is a compression test and the other is I use a heat gun to see
if there are any hot spots anywhere on the motor.

Worked on a 1974 6hp. Johnson
​Ran good but seemed to break down the longer it ran.
It had a new impeller and pumped great.
​The heat gun found 1 spot that shot to 175d + after it got warm.
​The crud was built up between the cylinders and water couldn't circulate.

Fill out the profile and add a signature with your location.
​Location can tell us a lot on how a motor was ran.
​Like if you say your from Ohio?? I'd figure the motors never seen salt water.

 

[Scott Danforth]

The impeller has been sitting in it unused for 25-30 years but was new at the time.

change the impeller.

they last 5 years PERIOD, whether you use them or not.

 

[Chryslerman123]

If you mean with it has taken a set that the vanes are bended and still has that position even if you pull the impeller out of the housing...........then that is the issue.

The vanes should be flexible and should flex in and out depending on have high the RPM is.
It will flex in if the RPMs increase and out if it decrease.

That is exactly what I mean. I will change the impeller.

 

[GA_Boater]

I'll vote for doing the impeller change.

You pulled the impeller out twice and didn't change it? Oh my! It's one of the cheapest things to do and failing to change can lead to some of the most expensive repairs.

 

[Chryslerman123]

The impeller needs to be changed!!!!
You could try flipping it over while you wait for the new one.
​If it pumps then?? you still need to change it.

Is this a salt water motor?
Did it get used in shallow water a lot?

These pics are from a running motor.
A HOT running motor.

​2 things I do to any motor I work on: 1 is a compression test and the other is I use a heat gun to see
if there are any hot spots anywhere on the motor.

Worked on a 1974 6hp. Johnson
​Ran good but seemed to break down the longer it ran.
It had a new impeller and pumped great.
​The heat gun found 1 spot that shot to 175d + after it got warm.
​The crud was built up between the cylinders and water couldn't circulate.

Fill out the profile and add a signature with your location.
​Location can tell us a lot on how a motor was ran.
​Like if you say your from Ohio?? I'd figure the motors never seen salt water.

I know nothing about the history of this motor other than it has sat completely taken apart, unused in a garage loft for 25-30 years. My dad aquired it at some point and took it apart but he doesn't remember why because it has been so long. He thinks it blew a head gasket. Luckily he bought all the gaskets new when he took it apart so I have them. He never put it back together because he ended up buying a new motor. Ironically, the outboard has a sticker on it that reads:1976 OHIO Outboard Motor. So it is from Ohio and I'm pretty sure it has never seen salt water. Not sure about shallow water use though.

 

[Chryslerman123]

Can you still buy an impeller for it? The old one has 10 vanes.

 

[GA_Boater]

Can you still buy an impeller for it? The old one has 10 vanes.

Check your model number. Chrysler parts listings for 20 HP motors are for 1973-78 and 1979-82. 73-82 are 6 vane and 79-82 are the 10 vane.

All years use the same water pump kit with 6 vanes - http://www.iboats.com/Boat-Parts-Ac...ed.1--filter.prod_name?q=sierra 18-3240&s=sol

1973-78 6 vane impeller only - http://www.iboats.com/Boat-Parts-Ac...ched.1--session_id.843203528&q=sierra 18-8903

1979-82 10 vane impeller only - http://www.iboats.com/Boat-Parts-Ac...ed.1--filter.prod_name?q=sierra 18-8901&s=sol

 

[Chryslerman123]

Thanks GA_Boater for the links! My motor is a 1971 but I think either of those impellers will work, but can I go from the 10-vane impeller that's in it to a six vane impeller? Do they both pump the same?

 

[jerryjerry05]

The pump is designed (6 or 10) to pump way more water than the motor needs.
Yes either one will work just fine.