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Premium Member
702 Posts
Discussion Starter #1
Hey guys what about does a cast big block ,alu heads,innercooler,cmi big tubes,blower full of fluids turn key about weigh???
Thank u

288 Posts
This might answer some of your question.

I was putting my engine back in my boat today and decided to run down to a scale and weight it before and after the engine went in. I weighed each axel so I figure the total difference in weight is the weight of the engine.

First the engine is an iron block bbc with aluminum heads. The iron heads weighed 89# each and the aluminum heads weighed 44# each. It has Dana marine wet jacketed exhaust and an aluminum intake. The pan is steel and the water pump is aluminum. It is totally set up and ready to run with alternator, starter, fuel system, wires, hoses,and everything. The heat exchanger is not connected to the engine so it is not added in. The engine has about 2gallons of oil in it.

The scale is supposed to be accurate to with in ten pounds.

Weights are:

Front axle without engine. 4400
Rear axle without engine. 4460
Trailer axle without engine. 3020

Total without engine. 11880. (much heavier than I thought it would be)

Front axle with engine. 4440
Rear axle with engine. 4300
Trailer axle with engine. 3920

Total with engine. 12660

Making the complete running engine 780. (much lighter than I thought)

I have never weighed anything in segments like this so I don't know if there are other factors to consider.

I am going to go back and weigh the truck without the trailer to see what the trailer and boat weigh. What is the weight of a tandem axle trailer for a 21' boat with surge brakes? I will end up weighing it at some point and figure out the weight of the boat from that.


109 Posts

Something isn't right how can your rear axle weigh less with the motor? you can weigh it if you can only fit 1 axle on the scales just make sure you only have 1 axle on the scales at a time do ur truck then trailer add them then do it again with your motor then minus the with out motor from with that's your motor weight. Makes sure your sitting in the car if your each time it's being weighed cuz you'll have a difference . Or go to your local truck stop and you can weigh the hole shit and caboodle at the same time. If you wana now how much your boat weighs with it go drop the boat in the water go back thatll tell you how much it weighs . Hope this helps.

Bostick Racing Engines
1,063 Posts
Something isn't right how can your rear axle weigh less with the motor?
Weight transfer.

Engine in the back of the boat transfers weight off the tongue and more towards the rear. Ever try lifting the tongue of a boat trailer with the engine out? It's friggen' blow yer o-ring out heavy.:))eek:)) Add the engine and have someone stand on the back... the task becomes easy as pie.

But all in all.. the overall and weight on the trailer axle should go way up... also so should a little bit of the front axle of the pickup.

I don't know how this scaling method could be super duper accurate... but as for getting a ball park... I guess it could work.
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