test running inboards

[waynes world]

While i am rebuilding my other engine, which are Volvo Penta AQ130`s, petrol inboards on 270 outdrives.

I was wondering today like i do whilst busy at work. I will be building a tank arounds the drives to test run the engines once fitted, to well give them a test run to check engines are good and drives work etc.

Now if i know these old engines like i do being the same/similar to the Ford Pinto carburetted engines they can run fine stood still and revved, but when under load can play up and run rough.

I could be overthinking this but if i can i want to ensure the engines are spot on before launch.

So am i over thinking tis or is there a way to put the engines/drives underload in the test tanks ?

 

[simonfraser]

be a quick way to get the water out of the tanks i recon

 

[Dellquay13]

Outboard motor dealers use special full load/ no propulsion plastic fake props for testing outboards in tanks, there may be something similar you can get hold of.
When I had a 90hp evinrude in the workshop 20 years ago for a tune-up the mechanic fitted his test prop.

 

[waynes world]

Outboard motor dealers use special full load/ no propulsion plastic fake props for testing outboards in tanks, there may be something similar you can get hold of.
When I had a 90hp evinrude in the workshop 20 years ago for a tune-up the mechanic fitted his test prop.

i have done this many times wit an outboard but for some reason i am thinking this will not give the same loading as the boat under power.........will it ? must be having onw of them moments when head is bit full.

 

[simonfraser]

to get the same loading as under power going forward you'd have to displace a lot of stationary water

in a container at best you're going to get the water swirling round, that is not what happens when afloat
or you'll be blowing it out of the top of the container in seconds at full power

not what i would want to do with a powerfull motor and a rotating prop
if the container empties / moves when on full power you're going to do serious damage

 

[waynes world]

to get the same loading as under power going forward you'd have to displace a lot of stationary water

in a container at best you're going to get the water swirling round, that is not what happens when afloat
or you'll be blowing it out of the top of the container in seconds at full power

not what i would want to do with a powerfull motor and a rotating prop
if the container empties / moves when on full power you're going to do serious damage

Well obviously yes it will throw the water out woth prop on gjve it the beans. Thats my point and question in is there j way I can not think of thay I can put it under load to test it properly.

Just an idea as said before its launched.

 

[Dellquay13]

The ‘frisbee like’ test prop the mechanic had didn’t empty the tank like the real prop would, but isn’t probably economically viable or easily available just for testing the engines once.

If the boat is on a trailer I would just back it in to the water enough to run the engines hard making sure the boat is secure on the trailer and the vehicle hand brake is on hard. That is what another mechanic did after servicing the outboard. The boat did try to push the trailer and truck up the slip, but didn’t manage to move it, just lifted the nose of the trailer coupling.