berns29scarab

buddy just purchased an 05 38 slingshot w illmor 550's n arnesons didnt get any water coming into the strainers unless engines were 1500 rpms or higher. my question is regarding the raw water pumps on the v-10's. do they use the same impellers as merc ? once run dry and over heated are they shot ? any assistence would be helpful.

thanks Bernie 732-539-5882

lavey jr

I know that the older Ilmors had a slight issues with the impeller sucking water at lower RPM's (start up and idle speeds)...
I can't speak for the 550 but I assume the 625 and 710 would be the same... The impellers are the same as Merc. And depending your setup and instalation if you have room, you can use and adapt a whole Merc housing/impeller system to the Ilmor.

lavey jr

Also, the older Ilmor impellers were designed to be able to run dry for a while, but they had to much flex and didn't suck as good...
Another thing to look at is if your sea strainer is to high above the water line, it will be harder to suck the water "up hill" into the strainer... If this is so, you could fill the strainer with water which will create the initial water pressure and help charge the impeller...

Hope all that helps.

Uncle Dave

Correct

There are 2 generations of pumps the latter pump uses a standard merc impeller and a different pump that looks like the hardin marine unit (very nice). It performs superbly, but requires a annual impeller change at a minimum.

Also correct on "charging" the strainers. Dont ask me how I know Lavey Jr. is right.

Uncle Dave

C_Spray

iTrader: (2)

That was the Miami Boat Show display boat that year, wasn't it?

IlmorDonzi

I change my Gen 3 Hardin Marine impellers every winter and they usually look fine. Are you saying the Hardin Marine units "require an annual impeller change at a minimum"?

berns29scarab

thanks for the input. it turns out they are Keith eikert bodies and the merc impeller is an unbolt n rebolt

Uncle Dave

I've replaced 4 impellers in two and a half seasons now.

One because I failed to "charge" the strainer and it ran dry too long.

The others were precautionary and I had vane cracks on each one I looked at that came out.

I think the price one pays for a pump with great suction is in reduced impeller life.



UD

fantastixvoyage

iTrader: (1)

Is this the boat that sat at Lake Cumberland for YEARS?! Always liked the idea but heard it was a bit of a handful. It was there back in '05 when I ran the two ilmor talons that were also there.

Have your buddy talk to ilmor about doing some upgrades. The 550s were pretty old school compared to what they are doing now (dress and power). Believe these had the coolers in the rear if I'm not mistaken.

C_Spray

iTrader: (2)

Ilmor is the primary sponsor of the New Jersey Performance Powerboat Club for 2011. If the owner is a member of NJPPC, he might be able to get some favorable treatment from Ilmor. I don't know for a fact; Imjusayyin...