[Mark Tripi]

Tom, I think this question has been answered many times. Looking at the pumps you might think a 6BT r/w pump would fit but it does not clear the P Pump. I have been over this road and got that info from Tony. After searching for a better way I made and installed a belt driven front mounted Jabsco pump that I under drove to match the water flow. It worked out perfectly. Another member here did it also and while I did it when I pulled my engines for other reasons, Dan did it in the boat. Maybe Dan will see this and join the conversation. The large Jabsco pump was so underworked they lasted forever. I did sell the boat last year but the system was trouble free and paid for itself in no time. The post is on this forum if you want to take a look.

 

 

[Mark Tripi]

 

 

The system made winterizing a breeze.

[Mark Tripi]

Tom I did get to the bottom of it. I hooked up boost gauges for both engines and my port boost was way down. I put on a new turbo and all was great. I sold the boat last fall and am about to sail a 36 Tiara Open down from The Saint Lawrence River via the Erie Canal. Twin QSB 425s in her. 

[Mark Tripi]

Steve, when I first started down this road I was thinking of driving it direct using a spider or “Lovejoy” coupling. To make it work you need to be spot on in your alignment. The belt drive while needing a good alignment is at least forgiving some in that aspect. My bracket is sandwiched between the block and mount. My friend Dan, also a member here, had welded up steel plate mounts so he just welded on an extension to his mount bracket and bolted the leg of the pump bracket to that. My brackets were cast so I went with the sandwich mount. Maybe Dan will step in with his view.

 

 

[Mark Tripi]

If you opened up the end cap can’t you use a pair of pliers to twist it while pulling it out? As they corrode they can flake and get thicker and sometimes break off. Over the years I learned to actually tighten them a bit (maybe 1/8 turn) before baking out. Never had one break after doing that.

[Mark Tripi]

Took these screen shots from my files.

[Mark Tripi]

Steve, the damper drive has a 40 tooth sprocket (P40-5MGT-25) and the Jabsco pump has a 52 tooth sprocket (P52-5MGT-25) on it. That under drives the raw water pump, the ratio is roughly 1.3-1. That was done to keep the water flow as close as possible to the Sherwwod pumps on my 4 BTAs. This is easily adjusted by the size of the sprocket on the raw water pump. You need about 15 inches in front to make it fit.

[Mark Tripi]

Sure thing Clark. In no particular order. Glad to answer any questions you have.

[Mark Tripi]

https://www.sbmar.com/community/topic/project-finished/ I vowed never to buy another Sherwood for my 4BTAs in 2019 and designed this system using a jabsco pump with a half thickness cam driven by belt off the front of the crank. Never a problem.

[Mark Tripi]

A few years ago I pulled my 4BTAs from the boat for some rehab and decided to fabricate a new raw water pump system to get away from the sherwood pumps. I took some time but I designed a bracket that was sandwiched between the block and the front motor mount. It is driven by a crankshaft mounted mandrel driving a 40 tooth timing sprocket and a toothed belt with a 52 tooth sprocket on the water pump. No reason you could not adapt that for your needs.

 

Project finished

[Mark Tripi]

No, I measured voltage to the solenoid which it had, but none leaving to the heater. Bad solenoid.

[Mark Tripi]

I painted both of my turbos with Rustoleum 2X, primer and then gloss white. Looks new a couple of years on.

[Mark Tripi]

That sounds great, this boat looked the same also but all the soft goods in the cockpit are shot. Aft facing seats and cockpit pads. Did you said her down or truck her?

[Mark Tripi]

Thank you Tony, I agree with you 100%. Here is a story for you. I listed my 30 Pursuit with 4BTAs, if you remember the one where I mounted a belt driven 3208 r/w pump in front of the engines. Had a survey and sea trial and all went well. Surveyor asked me why there was no water in my bilge (because I clean them)? Next day I get a call from my broker, the buyers backed out. Not sure who put the idea in the buyers head, surveyor or their broker. But the broker called my broker asking if the boat had sunk (it did not) because the bilges were too clean!

[Mark Tripi]

Thank you very much. That is very reassuring to see. What lake was the boat on?

[Mark Tripi]

I mean “insight”!

[Mark Tripi]

I had the same problem a few years ago. The problem is the rust from the turbo side has expanded and made the bolts even tighter. The quickest and easiest way to get them off is to cut them off with a sawzall or a hack saw blade taped on one end for you to hold. Once I did that I used a small pipe wrench to take the rest of the bolts out and it was easier to remove them than I figured. The rust on mine had expanded enough to bend the elbow mounting flange. I sent my elbows out to be rebuilt. Better check the turbos also. 

1 user thanked author for this post.

Robert McManus

[Mark Tripi]

Best I can do. You know I checked it again.

[Mark Tripi]

It does not take much to lose prime. One area I have had this happen on my 4BTAs is right at the connection between the return line and the injector, the copper washer. With a cold engine pump up your fuel system using the primer pump. When the pump gets hard to push check those connections. Feel them with your finger and see if you get any diesel fuel on there. 

[Mark Tripi]

I have Cummins 4BTAs. There is a hose connected to the rear of the oil pan at one of the drain plug fittings that is capped off. I attach the suction hose from the oil drain pump to that hose to remove the oil.

[Author]

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