alpha drives and crossovers.....
 

I just got off the phone with CP Performance and was told that a crossover and my AlphaSS drive will not work well together. It seems the small impeller doesn't flow enough water at idle, and causes overheating.
Has anyone tried this setup before?

What are you saying boatracer46? http://www.offshoreonly.com/ubb/smile.gif

Mark, That might be a circumstance where it might be better to go no bypass and use a restrictor to control flow? Why are you wanting to use a crossover? Stock setups are pretty hard to beat on non blown motors.

[This message has been edited by US1 Fountain (edited 02-26-2001).]

So boatracer46.....you sayin I should put a hull pick pu on it??? http://www.offshoreonly.com/ubb/biggrin.gif http://www.offshoreonly.com/ubb/biggrin.gif ;p lol

US1, I only want one cause everybody else's got 'em! http://www.offshoreonly.com/ubb/biggrin.gif Seriously, just thought I'd spring for some fancy add-on's. I finally paid the boat off and I'm trying to keep myself busy so I don't go out and buy a new boat! But, I might be easily pursuaded. Know any good deal on some 28 footers?

OK, I might not understand.....how will a through hull pick up flow more water at idle. I would need a seawater pump/engine driven to use this....right? My water pump is in the drive.

Boatracer46, are you running both waterpumps then? The one in the drive and a seawater pump?
If thats the case, the seawater pump alone would take care of overheating at idle.

[This message has been edited by Mark (edited 02-26-2001).]

heh heh....send me an e-mail with an in-depth explanation. I'll read it during work. Got all kind of time there. http://www.offshoreonly.com/ubb/biggrin.gif I really would like to hear about this, seriously.

I found this post using the search engine. The question about water pumps is this: Can a raw water pump be omitted if the water pickup is in the bottom of the hulls engine compartment? The boat is a 1974 Cigarette 28SS and the engine area sits low in the water at idle. I am not sure as how these boats came setup when new. This is a project I am working on and need all the help I can get!

My Formula has an Alpha and thought of going with a crossover and a transom pic-up. Was told I would have to use a Bravo type raw water pump.
The impellor in the drive must remain in place and working since the water flow through the drive supplies some cooling for the drive oil too. One suggestion was to use it to feed a drive shower.

My guess is that a crossover with a thermostat and standard bypass would not flow enough water (I just ran into this problem on a chris craft engine). A no bypass, no thermostat system would work though but it would be hard to balance engine temp and water pressure.
An engine mounted pump would work. It can supply enough volume at idle to run through the bypass and engine with the thermostat open. You'll still need your original drive mounted impeller working to pump water through the drive to cool it.
The other possibility is to put pressure valve in the bypass line. This will force water through the engine at idle with the thermostat. I did this on the Chris Craft engine and it worked great.
BTW, dont ask where to get a pressure valve. I had to modify a part that's no longer available.
Gary