76 chrysler 45hp 456hh impeller

[akwormy]

I just got this old motor and when I backed it in at the launch and started it for the first time I couldn't see any water out the telltale (couldn't see a telltale for that matter! but after some searching here see that it comes out the exhaust and no real stream). I took the thermostat out and there was no water circulating in the head at all so the water pump was obviously not working.

First off let me say it's a jet drive - so no regular lower unit.

I dropped the jet to get a look at the impeller and it looks fine, but I'm wondering if it's the right unit or if maybe something is wrong because it seems to me that it just spins on the shaft - it's not keyed or anything.

Does anyone know if the impeller is supposed to just slide over the shaft like that or is it supposed to be keyed somehow?

I verified that the water passages are not obstructed by forcing water up through the hose that hooks to the water pump cover and it came out the hose that goes to t-stat housing just fine.

Anyone know if the impeller and water pump cover shaft seal are the same as for a regular lower unit? In other words if I find these parts for this chrysler motor will they be right with the jet unit? (I've emailed outboard jets in CA, hopefuly they can confirm that for sure)

thanks

 

[Frank Acampora]

Re: 76 chrysler 45hp 456hh impeller

WOW! Is it a Chrysler jet unit? I know Chrysler did make inboard jet drives but I did not know they made outboard too. Pictures would be great!

In the outboards themselves, the impeller is driven by a stainless pin that sets in a hole in the shaft and a slot in the impeller.

For more info, if it is a chrysler unit, try dave or franz over at the Chrysler Crew.

 

[akwormy]

Re: 76 chrysler 45hp 456hh impeller

thanks - no the jet isn't chrysler, like most it's an "outboard jets" brand jet unit

I figured out a little more on this - here goes

when I took off the lower plate of the water pump (below the impeller) I saw the hole in the shaft that you mentioned - it was below where the impeller rides....so somehow the shaft was too low in the housing. After 20 minutes or so I realized how it happened...

(#35 in the picture is the shaft and towards the bottom of the shaft you can see the thicker diameter area - that bigger part rides in the bearing carrier #48)

anyway the thicker part of the shaft is a sleeve that is held on with a roll pin - somehow this one sheared the pin off so the shaft was no longer coupled to that thicker sleeve part. From there - the shaft must have worked it's way lower and lower over time until the impeller was no longer being driven!

anyway I was able to get what was left of the old pin out and I think if I can find a new pin and get ahold of a diagram (the one I attached is not for my jet, but it's similar) I might be able to get it all back together....maybe! (there's a lot of parts in that bearing carrier!)

 

[akwormy]

Re: 76 chrysler 45hp 456hh impeller

well the shaft and bearing carrier are sent out for repair/replacement...hopefully I get them back soon

Found a water pump impeller but can't seem to find the housing seal on the water pump housing where the shaft goes through.

any tips?