Alpha vs ahpha gen water flow

[crazy charlie]

Anyone familiar with the water flow from each.I looked closely at my alpha drive from the intake screens all the way thru the upper and was surprised at how small the passage ways are and the tube diameter in the upper housing.Curious if a gen 2 drive has a higher out put of water?? Charlie

 

[Bondo]

Re: Alpha vs ahpha gen water flow

Ayuh,.... Hi Charlie... The Alpha 1 is the short vane impeller, 'n 1/2" flow tube...

The Gen.II has a much longer vaned impeller, 'n moves considerably more water through the same 1/2" tube....

 

[crazy charlie]

Re: Alpha vs ahpha gen water flow

Anyone know if the gen drive is interchangable with the alpha one.Charlie

 

[Fishermark]

Re: Alpha vs ahpha gen water flow

They are not interchangable.

 

[crazy charlie]

Re: Alpha vs ahpha gen water flow

You have probably answered my last question correctly but I will rephrase it to be sure.Can I replace my alpha drives with gen 2 drives for increased water flow?.Charlie

 

[haulnazz15]

Re: Alpha vs ahpha gen water flow

No, the Alpha Gen II will not bolt up to the Alpha I bell housings. Why do you feel you need increased water flow? the Alpha I's had no problems with cooling when bolted to small block V8's, and many Big Blocks as well.

 

[crazy charlie]

Re: Alpha vs ahpha gen water flow

I have had a rising temp at idle problem on both motors for a number of years now.I have replaced just about everything involved with cooling and still have the same symptoms.Thought for a moment that I may have the wrong drives on it.Charlie

 

[Don S]

Re: Alpha vs ahpha gen water flow

Do your engines have a FULL closed cooling system (Including the manifolds) on them?

 

[crazy charlie]

Re: Alpha vs ahpha gen water flow

My system is a raw water cooled . 1988 5.0xl mercruisers with alphas .By "closed" do you mean fwc??

 

[Don S]

Re: Alpha vs ahpha gen water flow

By "closed" do you mean fwc??

Yes, but since you are raw water cooled, it doesn't matter. You have a problem with your system, problem is finding it. Changing to a bigger pump is only covering up the problem.
Have you checked the water hose between the drive bellhousing and the transom shield for kinks? Another thing overlooked if you boat in salt water is shells blocking the tube that goes through the bellhousing. They can get hung up in the sharp bend.

 

[crazy charlie]

Re: Alpha vs ahpha gen water flow

Thanks Don.when I bought the boat,I did what I usually do with a new(to me)/used boat,replace the entire transom kit including the hose,o/d impeller kit,circulator pump on engine,manifolds and risers and tstat.I like to start out with all of this new.I will check the hose anyway and possibly try to snake it out.I fresh water flush the motor after every use .Cant figure it out.Charlie

 

[dubs283]

Re: Alpha vs ahpha gen water flow

check the oil coolers for blockage too - weeds/debris

one check is to remove the supply hose at the t-stat housing and run the engine, watch for good flow out the hose end

there is a spec for amount of water in a certain amount of time for specific drive ratios - check the manual for that

 

[Bondo]

Re: Alpha vs ahpha gen water flow

I have had a rising temp at idle problem on both motors for a number of years now.I have replaced just about everything involved with cooling and still have the same symptoms.

Ayuh,... Do your T-stat housings have the Check-Balls,..??
Did you use the Right riser gaskets,..??

 

[crazy charlie]

Re: Alpha vs ahpha gen water flow

I plan on removing and checking the p/s coolers.YES Bondo ,I DO have check balls in the tstat housing.Charlie

 

[crazy charlie]

Re: Alpha vs ahpha gen water flow

Ayuh,... Do your T-stat housings have the Check-Balls,..??
?

Why do you ask?? Charlie

 

[Bondo]

Re: Alpha vs ahpha gen water flow

Ayuh,... The Alpha 1, with the lower flow pump, Needs the check-balls to hold back the water slightly,...
But only at Idle....

I put a 4.3LX in my barge years ago,... The hull a 74, motor was a 93/ 94, the drive/transom an 83/84....
That's a hull for a Mod.1, a motor for a Gen.II, 'n the drive an Alpha 1....

I fought an overheat at idle for Years...
Finally, Last year or the year before, it struck me to what the Problem was, after readin' Don's response to another poster...
I realized my housing was Ball-less...

I scrounged up a T-stat housing with Check-balls, 'n the Problem totally Disappeared...

So,... What rpm do they idle at,..??

 

[crazy charlie]

Re: Alpha vs ahpha gen water flow

I idle at 800ish rpms. I tried idling w/o the balls in place and same rising temp at idle.I am going to try to snug them up a bit to see if any difference.Strange thing is that I purchased a freshly rebuilt upper alpha to keep as a spare.When I put it together with a spare lower that I had and put it on my stbd motor last year,it ran at 145 and never moved for 2 seasons.....until last week.Same crap is back.Thought it may be the gasket under the water pocket in the upper since there was a new one in the upper that I bought.So I had it replaced in my other drive and no difference.As far as the riser gaskets,I used the ones that came with the Osco Risers.The gaskets had openings on 2 sides,not all 4 .Sound correct?? Charlie

 

[crazy charlie]

Re: Alpha vs ahpha gen water flow

I guess I should remove a riser and have a look now that you got me thinking about gaskets.

 

[crazy charlie]

Re: Alpha vs ahpha gen water flow

Are the open part of the riser gasket supposed to be lined up with water flow por on the sides??