470 Impeller change

"Well after 2 months of repair

"Well after 2 months of repairs, exhaust manifold,(leaking cooling chamber into the exhaust and into the head head) completely rebuilt head upgrade to 4" heat exchanger, new plugs, new lifters I started it and everything seemed to be fine, but a fair bit of steam out of the prop. The temperture on the gage did not go about 140 degrees, not under load of course and kept RPM's below 1500. Does this sound Ok temp. with a 160 thermostat So now I am going to replace the impeller kit. I have the complete upper and lower drive off and in my garage so now do I use any lube on the impeller, and what to use on the gaskets on "O" rings. Should be ready for Pender Island again next summer. Cheers and thanks"

Gaskets are installed dry. Pa

Gaskets are installed dry. Pay close attention to their order. A dab of 2-4-C on the "O" ring. A little dish soap/water for lube to install the impeller. A manual is a big help.

"Hey rising Sun I am in the sa

"Hey rising Sun I am in the same position, we should trade pics! I dragged mine to the basement shop but I haven't torn my outdrive apart yet as I am waiting for a rainey weekend to start. Too many house projects to complete before winter.

I bought the impellor kit from this site for around $30 including the SS cup base. As suggested to me on this site, pressure test the whole unit before installing back on the boat and dropping in the water. I noticed the gasket that came off between the unit and bell houosing has built in rubber type cement but the kit I bought doesn't. I am thinking of adding a slim stream of gasket sealer to it for kicks and grins. Or am I crazy? Also thinking of replacing the u-joints as they had some moisture and rust colored grease. Another project for this winter is to rebuild my closed cooling system waterpump.

140 degrees F seems about right. Mine runs consistently at that temp. Of course who's to say my 27 year old temp gage is right on but it is consistent.

Hope to see you in the Islands next summer. Boy I hate this time of year."

"Hey PS, how u doin. I have ta

"Hey PS, how u doin. I have taken the unit apart and the impeller does not have to be replaced as it is in excelent condition. Replaced a year ago and has only about 20 or 30 hours on it. I wanted to check it out anyways after I had all those problems on Pender Island this summer. Now can someone tell me how to pressure test the unit, and does this have to be done with the upper and lower together? And I also will be using some gasket sealer on that gasket between the upper unit and the bell hsg. My boat is a 1978 Glasply built there in Washington as u probably know with the MCM470 closed cooling and it does have the Pre-Alpha outdrive. I would like to upgrade the charging system to the Alternator type and go also to HEI distributor,in the spring any sugestions where to buy from in the Pacific Northwest? TTYL. I'll try and send some pics as soon as I learn how to upload the ones I want. Cheers"

"Hey RS

I have two reasons

"Hey RS

I have two reasons for spltting my unit. One is I believe the leg was replaced and with the wrong ratio; 1.98:1 instead of the correct 1.84:1. I bought a good 1.84 unit off of ebay that was used in freshwater only for $180 delivered. And two as I pulled the end cap off the heat exchanger I found a little piece of impellor. So the pump will be replaced.

You can pressure test the whole unit together by installing the upper vent screw and rigging a bike tire pump with a gauge to the oil drain hole. I'm going to rig something with my gear oil hand pump hose that screws into the oil drain whole and clamps and hose. I haven't done this yet but If I figure it out I'll post it. But if it holds air pressure with the new gaskets, you're golden.

As far as the alternator conversion I haven't found any better or cheaper locally than just buying online from Breezeworks.com. You have a choice of upper or lower mount from them. As far as HEI distributor that might be difficult to find for the 470 but FWIW I love my Pertronix ignition system for less than $100. Accomplishes the same results like easier starting and smoother idle and isn't really affected by heat or moisture. Good luck and ask away if you have more questions."

"Here is a link to what I own

"Here is a link to what I own and use to test outdrive pressue,
Pressure check is to ~15 psi and it should hold for 2 minutes.
Vacuum is ~ 4-6 inches and hold for 1 minute.

I know they are expensive but at least it gives you a idea of what it should look like if you choose to make your own.

The thread of the drain and vent hole is 3/8-16


http://www.stevensinstrument.com/gearcase.htm"

I found a vacuum line adaptor/

I found a vacuum line adaptor/connector and stuck one end in the end of my bike pump and the other in the end of my gear oil hand pump hose and it worked great. Good enough to find out my donor upper has a massive oil leak in the drive carrier bearing seal. So much for buying a "good" used upper unit. Thanks for the advice Kghost.

"Weel if it dosent work out ,

"Weel if it dosent work out , I have that drive (1.84)available ,fully serviced ,ready to go."

"Bt Doctor, where are you and

"Bt Doctor, where are you and how much are you asking? You can PM me off the board. Thanks."

"Just a few pics of my pressur

"Just a few pics of my pressure tester. Works great. I got 20 psi no problem.

I went to the auto parts store and found a vacuum line adaptor 1/4" x 3/8"





Then plugged one end into my gear oil pump and the other onto the end of my bike tire pump with a pressure gage;




Plug her in and pump up to 20 and hold.



Then pull it apart and put the pumps back together."

Ed you want that gimble ring f

Ed you want that gimble ring from the alpha one sitting behind Ritcies house.

I don't want nothing for it just come and get it.

Maybe you can clean it up and sell it.