1970 Chrysler 55

[ecgregory@rcn.com]

hey i have a 55 hp chrysler and i cant figure out whats wrong. first of all, at an idle water only spurts out the hole in the back. When i put it under a load in the water, the engine overheats. I replaced the impeller and this didnt change anything. I thought maybe the thermostat was no good so i took it out and ran it and water still wasnt coming out as a pressured stream. Anyone have any ideas? I would really appreciate it.<br />Thanks,<br />Nick

 

[WillyBWright]

Re: 1970 Chrysler 55

Welcome to iboats. <br /><br />Sounds like exhaust is getting into the pump. That's usually from a bad seal on the pump housing, but more commonly due to a worn pump housing.<br /><br />Chryslers didn't have telltales. Only the exhaust relief holes on the back of the motor where water will spray out. It won't come out of there in a stream.

 

[eurolarva]

Re: 1970 Chrysler 55

When you replaced the impeller did you remember to use the impeller key? Is the impeller fins pointing the correct direction? Put the impeller on the impeller key and push the water pump down hard on the impeller while slowly turning the drive shaft clockwise until water pump is completely seated. I am pretty sure there is no seal on the water pump but it could be pitted as willy mentioned. I have seen the glue separate on the impeller with the brass inserts where the brass insert will spin in the middle of the rubber impeller. It will work sometimes at idle and then crap out at higher rpm. Also make sure the water tube is connected to the grommet going to the powerhead. It is possible to install this incorrectly. I install the water tube into the grommet so it hangs by itself when I attach the lower unit.

 

[jmk]

Re: 1970 Chrysler 55

Hi, My name is John and I am about to do this impeller change on my 71 55 hp. Do you spin the impeller counter clock wise when putting it in like the three and four cylinders? I bought a manual of e-bay before the parts and the parts arived first. I did my 35 hp Merc last year and getting the gears lined up took me about six times! Once I changed that one the motor even idled better. The impeller had all the fins gone! Well, some wern't gone they were still bounceing around in the pump. LOL... My Chrysler has three sections. Do I need to unbolt the middle one too or just the bottom one? The people I bought my impeller from said that there is no gasget that it's just a plat and all I need is the impeller to do the switch. Is this true? If no gasgets do you put sealer on both sides of the plate?

 

[AuSable Junkie]

Re: 1970 Chrysler 55

jmk,

I'm getting my new impeller for my 1969 Chrysler 55 hp tomorrow. I've had the lower unit on and off the motor for a week now, replacing seals, testing for water leaks, and lastly, the impeller.
Sounds like you have a 2-piece lower unit like I have. If that's the case, then you only need to remove the four bolts lowest on the motor leg along with the shift linkage. Take the 6 small bolts off of the motor leg covers to get to the shift linkage. Its the 2" nut topped by the smaller stop nut. Make sure to mark the position of the stop nut so when you reassemble it, the shift linkage will have the same placement.

I clamped a set of Vise-Grip pliers to a wide slot head screwdriver and used it to remove the 3 bolts to get to the impeller. I couldn't muster enough leverage to break the screws loose with just my hand on the screwdriver. The drive shaft kept interfering with my knuckles as I tried to break the small bolts lose. I was afraid of ruining the slot at the tops of the screws by doing it that way. This was before I knew I could just pull the shaft out of lower unit LOL. Woulda made the knucklebusting a moot point.
Still, the Vise-Grip gave me more leverage and let me put more down pressure on the top of the screwdriver (left hand on the pliers, right palm pushing down on top of the screwdriver) to keep it in the slot. They all broke loose pretty easily this way.

If your lower unit is the same as mine, there is no gasket like you were told.

 

[jmk]

Re: 1970 Chrysler 55

Thanks for the help. I think my service manual came today. I need to read up yet. I'll keep the vise grip handy. It doesn't sound like it will be to bad of a job. I got my dog fence in today. Our Yorkshire Bentley got a shocking experience when trying to leave the yard several times today. It works great. Now a few more trips with the firewood and I will be able to start working on the boat! Yippee! I am going to rebuild the carb too. How hard was it to put the new seals in? I have a 35 hp Merc that gets water into the bottom, and I haven't checked this Chrysler yet. I have been just changing out the oil on the Merc. It would be nice to get it sealed.