Strainers for engines on 3807

[VicB]

Hey guys,
I have an 88’3807. It did not come with raw water strainers for the raw water cooled engines. Has 1-1/4” lines from the seacocks to the raw water pumps. I ordered Perko strainers (1-1/4”) due to a stopped up oil cooler. I am assuming adding strainers would only be a plus. Any reason that no strainers would be a better design. I got 1-1/4”. Due to mounting constraints, looks like I’ll need elbows for fittings on both sides. Would that small of constriction with elbows vrs straight fittings even be an issue? Any thoughts on this issue would be great.
Thanks in advance
Vic

[km1125]

Use the sweep elbows instead of the 90 degree ones... they flow much better. They're a little more expensive but worth it rather than having to upsize.

The only real downside is more things to maintain. Need to keep the strainer clean, but if you'd be getting junk in there then better there than in the engine coolers!!. Also need to make sure that the seals are good and you can't suck in air when the engine is really pulling in a lot of water.

[Viper]

I agree with km, use Perko's elbows specifically designed for that purpose, they won't add any notable restriction. Funny you should post this, I'm doing the same on my 3807 this season. Got them for the main engines and generator.

[mjk1040]

Most of the Carvers with Crusaders that I have seen do not have raw water strainers! Our 1986 and our 1998 never had strainers and I too installed them on the 1986 just before I sold her. Not planning on installing them on the 1998. Instead I treat the engines with a RydLyme to open up the passages through out the engine and the coolers. Take note that there multiple size screens for the strainers and you don't want to get too small of screens.

[VicB]

BCD6A460-6476-4ECF-85BB-D7E6A38D4BC3.jpeg

Good deal. Kind of along my same way of thinking. This all started last weekend when my port engine started overheating. Turns out my oil cooler was stopped out with remnants of an old impeller and some river debris that looked something like sawdust. I know strainers wouldn’t have stopped the impeller, but I was hoping that they would help the health and longevity of the engines. Viper when you figure out where to mount yours, I’d love to see some pics. Not a lot of room there as you know.

[VicB]

MJK, how did you install the Rydlyme? Also did you circulate it or just get it in the engine, let it set and flush it out?

[km1125]

Always thought it would be a good idea to have a strainer with a clear case between the raw pump and the engine. Seems like you'd just need a screen just SLIGHTLY smaller than any of the passages downstream, but it would be quick visual if you lost any vanes on the impeller and it would prevent them from getting lodged anywhere downstream. You can always lose some vanes even on a fairly new impeller, not just the old rotted ones.

[VicB]

Here is what is interesting about the picture. I replaced impellers in April. The ones i took out had all their vanes. This must have been an old impeller somewhere way back. All that debris was just past the 90, on top of the tubes. I could barely feel it with my finger through the opening. How could all that packed in that little chamber go for years before finally restricting water flow? This included a 90 mile trip from where we bought the boat to our home marina.

[bud37]

Lots of times those pieces lodge themselves right at the pump discharge and are hard to see if not looking......put new impeller and pressure and flow is higher then these pieces move along and collect in one spot creating your restriction.....just my opinion....

This rydlyme is basically approx 9% HCL to remove lime scale....I think a strainer in the system is there to keep all the big stuff like sea grass and debris out, two different purposes......really depends on where you boat.

[Viper]

Source of the post......Viper when you figure out where to mount yours, I’d love to see some pics. Not a lot of room there as you know.

I'm thinking on the outboard side of the centre stringers behind the engines.