292 inline 6 with prealpha drive for 19.5 cuddy

RDTBC

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this would grenade your motor. there are different balance requirements between the 250 cubic inch and the longer stroked 292
Ok. Good to know.

I’ll start investigating options for side motor mounts. I don’t think there are any off the shelf solutions. As far as I know, side mounts are all designed for V-blocks, so I’m thinking I’ll have something fabricated from steel in an L shape which will bolt up to the triangle bolt pattern on each side of the block. Then, I’ll reinforce the stringers and install two rubber mounts (from a typical V side mount).
 

achris

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Ok. Good to know.

I’ll start investigating options for side motor mounts. I don’t think there are any off the shelf solutions. As far as I know, side mounts are all designed for V-blocks, so I’m thinking I’ll have something fabricated from steel in an L shape which will bolt up to the triangle bolt pattern on each side of the block. Then, I’ll reinforce the stringers and install two rubber mounts (from a typical V side mount).
That is exactly how I'd do it. Fabricating a couple of side mounts wouldn't be difficult. I'd probably use a couple of 'normal' V engine mounts and modify (extend) them. Or just build a 'packer' to go between the engine and the mount.

Chris.......
 

Scott Danforth

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That is exactly how I'd do it. Fabricating a couple of side mounts wouldn't be difficult. I'd probably use a couple of 'normal' V engine mounts and modify (extend) them. Or just build a 'packer' to go between the engine and the mount.

Chris.......
you could buy the bayliner side mounts that they used on the 3.0 I believe they are a brunswick part
 

achris

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RDTBC

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Here’s a progress shot of the 292. I installed the timing cover, original triple pulley harmonic balancer and oil pan tonight.
Nothing like a 5 gallon overhaul and some brass freeze plugs to sharpen up an old motor…
 

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oldsub86

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Do any of you folks have personal experience with the 292 Mercruisers? I gather they are fairly rare as they were only used for 1 or 2 years. I have heard they were hard on fuel. I had a 1968 Chevy C10 pickup with the 292 and a 2 speed powerglide transmission and it was hard on fuel. Part of that may have been the 2 speed transmission.
I knew a fellow who had a Glaspar boat with the 292 as the original engine but by the time I knew him that motor had been replaced with a V8 with an updated outdrive as well so I don't know much about his experience with the 292. I believe the boat was old when he got it and he did not run the 292 very long as it was worn out. It was less expensive to replace the whole unit than it was to do a proper rebuild.
 

Scott Danforth

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Do any of you folks have personal experience with the 292 Mercruisers? I gather they are fairly rare as they were only used for 1 or 2 years. I have heard they were hard on fuel. I had a 1968 Chevy C10 pickup with the 292 and a 2 speed powerglide transmission and it was hard on fuel. Part of that may have been the 2 speed transmission.
I knew a fellow who had a Glaspar boat with the 292 as the original engine but by the time I knew him that motor had been replaced with a V8 with an updated outdrive as well so I don't know much about his experience with the 292. I believe the boat was old when he got it and he did not run the 292 very long as it was worn out. It was less expensive to replace the whole unit than it was to do a proper rebuild.
the motor burns 0.4# of fuel per HP per hr. nothing special about the BSFC
 

RDTBC

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I recently fired up the 292… and it ran! And it didn’t blow up! Getting ready now to prepare the boat to receive the engine.

I have a radiator and am planning to do a full fresh water cooling system on the engine. I’ve installed a block off plate between the elbow and exhaust manifold. I plan to plumb it as shown in this San Juan drawing. My thermostat housing and water pump each have threaded 1/2”NPT holes, but the manifold has larger hose nipples (I think 3/4” NPT). I’m planning on using adapters to increase the size up to match, but those little holes will restrict the flow. Does anyone know if these small 1/2”NPT holes on the thermostat housing and water pump will allow for sufficient water flow to cool the manifold?
 

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Scott Danforth

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Get the appropriate thermostat housing for raw water cooling 1/2" NPT is a bit small.
 

Scott Danforth

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I recently fired up the 292… and it ran! And it didn’t blow up! Getting ready now to prepare the boat to receive the engine.

I have a radiator and am planning to do a full fresh water cooling system on the engine.
I hope you mean heat exchanger
 

RDTBC

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Get the appropriate thermostat housing for raw water cooling 1/2" NPT is a bit small.
Thanks. I see that this style is available for purchase, but it looks like the thermostatically controlled outlet at the top (which would go to the heat exchanger) is only about a one inch hose barb, but the heat exchanger accepts 1 1/2” hose. Will a one inch hose to the heat exchanger provide adequate flow? And I guess I’d have to block off the 1 3/4ish hose barb. Can anyone recommend a better style thermostat housing that would fit an inline 6 Chevy block?
 

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Scott Danforth

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Which heat exchanger are you using?

Is it sized for full-system?

Before you buy parts, you need to have a schematic.

That will determine which thermostat housing and how it's plumbed.

A full system requires constant flow to exhaust manifold and back thru HX and then to water pump, and the thermostat is used to mix as needed to control temp.
 

RDTBC

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I have a heat exchanger which I don’t know much about. No branding or model numbers on it. It’s about 2ft long and 4inch diameter with two rubber caps that are hose clamped onto each end. I’ll snap a picture and post later today. I was planning to follow the schematic a few posts above, but it dumps the hot water from the manifold right back into the block at the pump.
 

Scott Danforth

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Need to know specifically the length of the bundle, the number of tubes in the bundle and the number of passes. It may not be an engine heat exchanger
 

RDTBC

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I’d call it a two pass HX, with 67 tubes on each side, for a total of 134. It’s 4 inch diameter X 27 1/2 inches long.
 

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Scott Danforth

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Looks like a 2-pass

It would be fine for a half system

Would have to run calculations to see if it will cool a full system

Will sketch two schematics

Do you have an expansion/overflow/de-areation tank?
 

RDTBC

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yes, I have an expansion tank with the filler neck and overflow tube. I assume this takes care of deaeration.
 

Scott Danforth

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yes, I have an expansion tank with the filler neck and overflow tube. I assume this takes care of deaeration.
Got a picture? Have dimensions?

You will need about 2 quarts of expansion volume
 
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