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Help identyfing drive and engine

M

mschwartz

Member
can some one help me identify

can some one help me identify and out drive and motor. i bought a 1979 grady white marlin last year i have rebuilt the engine it is a chevy 350cid v8 cast in 1978 and the out drive is volvo penta. im not sure what drive it is maybee an 270/280/290 drive. the drive has a mechanical tilt mechanism but no trim. it has serial numbers but no model number would really appreciat help identifying so i can order proper parts in case of repair
 
"There is a plate on the drive

"There is a plate on the drive just next to the top rubber boot on top. The first 3 numeric digits should be the model #, i.e. 250..etc. The letter stamped at the end (and often barely visible) denotes the drive reduction ratio. For a 350 CID it should be a "B"."
 
"Regarding the engine/package

"Regarding the engine/package type, check for a brass plate attached to the engine block above the starter. It should have stamped something like AQ2xx-A or AQ2xx-B as well as the engine serial number."
 
I checked on the engine by the

I checked on the engine by the starter there was no identification plat there. On the stern drive unit the number was 2826821 followed by a b or d could not make out the letter it was worn off. Is it a safe assumption that the out drive is a 280? thanks for your help
 
"Yep...it's a 280! It SHOU

"Yep...it's a 280! It SHOULD be a "B". If you remove the prop and the zinc "ring" (and the line cutter) behind it, you should see the reduction ratio stamped in the housing next to the prop shaft. In reality, the number stamped after the paart number only "theoretically" defines the reduction ratio. Theoretically assuming its not a "frankendrive". Being a "fankendrive" is not necessarily a bad thing since Volvo drives are rugged and often folks repair them by "swapping" parts. While the letter determining the drive ratio is stamped on the plate on the top section, there is nothing in the top section of the drive that determines what the reduction ratio really is. That is determined in the bottom section...hence the ratio stamped on the housing. If the reduction ratio is incorrect, it will be almost impossible to get the correct size prop on the boat, i.e., that prop that allows the boat to rev up into the Wide Open Throttle (WOT) range for the engine at full normal load. This is critical since observed WOT RPMs either above or below the specified range are bad for the engine.

If the engine is out of the boat, you can also determine the actual ratio by putting the drive in gear and counting how many revolutions it takes to get the prop shaft to turn exactly 10 times. In your case it should be 16.6 revolutions of the input shaft."
 
"Mike, there should be a plate

"Mike, there should be a plate in that area if the engine block came with an original AQ package. Of course, many things could have happened over the years: the plate could have been removed, or painted on, or the block could have been renewed, or you may have an engine (either automotive or marine) that came from a source other than VP.

248278.jpg


248279.jpg
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thanks for the pictures el pes

thanks for the pictures el pescador they helped but there is no engine identification there. I hade the whole engine out and all the numbers on the engine were for gm marine. is there a standard engine number to go with the 280 series drive or should i use the gm numbers when ordering parts. once again thanks guy for your help
 
"Hi All, Does anyone now how t

"Hi All, Does anyone now how to figure the torque output at the prop, I am looking for Lb/ft at the prop. And I'll tell you why, maybe someone has some insite that can help. I inhereted a 30 foot 85 Century hull, twin inboard with no motors or transmissions, I was toying with the idea of hydraulic motor drive and hydraulic pump driven by a smaller single engine. I can get Hydraulic motors that can run at 3000 rpm and produce effective torque to roughly 80-85 Ft/Lb. I have enough info to calculate everything BUT the prop torque load. I am assume that a standard V8 configuration would put out in the neighborhood of 180 FT/LB torque, but what is the effect torque devlivered to, or at the props, through the trans etc."
 
"mmmmm... This is an I/O orien

"mmmmm... This is an I/O oriented forum. You are asking about losses thru an inboard transmission.
For your purposes, I'd assume about 5% loss.
That said.... not sure what you'd accomplish.
Yes, you'd save one engine, but where would you mount it. A boat designed and built for twins would present some issues locating the engine in the middle. Also... there is no such thing as a standard V8 engine torque. Assuming that your estimate of 180 ft/lb is correct,hydraulic motors/transmissions are fairly "lossy"... and trying to get a boat to move with a total of 170 ft/lb of available (max) torque to the props when it used to have almost 360 available, is problimatic...unless you won't be in a hurry to get anywhere. 3000 rpm at 80-85 ft lb torque to each prop won't get you much. According to my calculations, that's about 48 HP at the prop shaft????. That's like trying to power your 30 ft boat with a pair of 50HP outboards!...which given their lighter weight than a single V8 plus hydraulics would probably work better..."
 
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