What size strainer on a Chevy 305 v8?

radial

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Hi All,

Here's a question that I hope someone just knows the answer to, that I have been finding hard to work out...

What size strainer (in l/hr) do I need?

I've got an old Chevy 305 5.0 v8 hooked to a Penta 280 drive with I think a Johnson or Yanmar impeller and unknown water pump. Hose diameter on the pickup is 25mm from the drive and then the widens to 32mm in the engine bay.

Any ideas? :)

Thanks in advance
 

QBhoy

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They don’t usually have a strainer in place up that end. Not on an outdrive set up.
 

GrahamHR

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True, had 5.7 ( 350 CI) V8s on our first 2 boats. No strainers or filtration on the raw water side. Both had closed cooling with heat exchangers ( my choice, money well spent!)
 

Fishtigua

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On some race boats, we fit water pick-ups and strainers. The strainers act as a reservoir when when the drives are airbourne at over 70kts.
 

Freebee

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probably not fitted because when/if strainer blocks you wont know till temp rises and next heads is/are blown, i would suggest only fit if you are going to fit accurate alarm that has audible output.
 

radial

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probably not fitted because when/if strainer blocks you wont know till temp rises and next heads is/are blown, i would suggest only fit if you are going to fit accurate alarm that has audible output.
Perhaps, but it seems more likely that ingesting crap would block the cooling passages in the engine block before its able to block a strainer up completely. The passages are so small in some places that you could end up with localized overheating and destroy the block before the temp alarm even got close to triggering.
 

bowler

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The V8 in my ski boat has a strainer but that's on a shaft. All sorts of crud ends up in it. The alarm has never gone off. Haven't seen one on a stern drive yet.
 

Freebee

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i think the water suck up by a sterndrive is slightly strained by the gills cast into the drive water inlet. but op wants an inline strainer
 

QBhoy

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Simple truth is…you don’t need one on the usual, common and most numerous variants of the GM Petrol stern drive. If there is or has ever been an engine to put a tangible reference to description such as “bombproof” or “tried and tested”…It would be these things. Quite simply…there just isn’t anything to rival their half a century (to date) of trustworthiness and reliability so far. Nothing comes close. Basically…they’ve managed fine so far, without additional raw water filtration (over and above the as built)…to date. Best leave them as they are, I’d suggest.
 

GrahamHR

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Simple truth is…you don’t need one on the usual, common and most numerous variants of the GM Petrol stern drive. If there is or has ever been an engine to put a tangible reference to description such as “bombproof” or “tried and tested”…It would be these things. Quite simply…there just isn’t anything to rival their half a century (to date) of trustworthiness and reliability so far. Nothing comes close. Basically…they’ve managed fine so far, without additional raw water filtration (over and above the as built)…to date. Best leave them as they are, I’d suggest.
Agreed, but fresh water cooling makes them even more bomb proof ! (OK, an anode for the heat exchanger needed each year. I made my own for years from old outdrive zinc anodes in a home made aluminium mould; probably well less than £1.00 each for the burner gas).
 
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