Prop for a 140 'Rude

[brocluno]

OK, I have a hull and a used 140 V-4 crossflow. Hull is 16' deep vee Marlin (same as Tahiti, Sidewinder, Kona, etc.). Contemplating a pad, but let's just assume we can run for a while w/o it. Lo-Pro deck style.

OK, assume prop shaft is 3" below keel line with room to go up a bit on OEM gearcase. Hull is devoid of upholstery, carpets, and other niceties. Just two race seats, controls, fuel (8 gallons), battery and gauges.

What prop?

[phillnjack]

depends if going to use it on a very calm lake or in a bit of rough stuff.
for speed the 13 3/4 x 23 slver streak/srx was the original go fast prop for the v4 crossflow,
or a 131/2 x 23 sst. or the 13.5 x 24 raker.
any of these should get you to 60mph plus providing the motor can get to 6,000 rpms.

what year is your crossflow v4 140 ?
the fastest straight out the crate was the 1977 140 with its special tuner.

[brocluno]

Motor not here and I have not decoded the numbers, but I think it's a 76 for some reason ...

[David]

I recently sold a 16' Baja that we had a 115 HO Etec on. It would run on the rev limiter at 60 with a 24 Raker and a DAH 23 SRX. 64 with a Ron Hill Hoss copy, same with a small ear chopper (re-hubbed).

its possible our motors make similar power

[phillnjack]

if its a 1976 then it aint a 140. 76 would be a 135 (best looking engine cover I think).
first year of the v4 140 crossflow was 1977, it has the bubbleback exhaust and special race tuner.

[brocluno]

This is a bubble back for sure. I know that for a fact. I looked for that when we went to pick it up.

Spent this afternoon working on the hull and floors. Didn't touch the motor. Next work day it'll get more attention. I'll get numbers to decode, etc.

LU very nice with clean fin and no dings. Existing prop looks shallow (prolly a 17 or something), but again no dings and clean un-bent blades. So I'm thinking it was not abused. Paint's a bit faded, but not bad. All the decals are decent.

Fixed the leak in the OMC tank. Someone had smashed the hose "ear" on one end and it had broken the spot welds, so it was taped over and leaking. I cleaned it all up and JB Welded some SS sheet metal screws into the three spot weld holes and it's good now. Shot a little Chevy Moly Orange over the worked area and it just looks like a fisherman's tank now. Good enough for work on the stand and test fires

Got a Mueller 8 gallon square strap-in plastic tank for the actual boat

Next work day we'll get the motor up on the stand and wired so we can test fire

Thanks for the prop suggestions. Keep it coming while we work through this stuff

[phillnjack]

you need to post up a couple of pics so we can see everything before you make it look nice and pretty. ha ha
take a pic of the back under the bubble back exhaust in the thermostat area, soon see if she is a proper 140.
loads around that are realy 115 and even 85 with 140 decaled lids.
dont be surprised if its a pig to start, the 140 was not exactly on the button when cold, but once fired up they will run all day.
nice compact engines, so good that Yamaha copied them .
check the wires going to the coils carefully, these are prone to breaking due to age etc.

[David]

3 inches below the pad worked for me when I had a 100 GT on my Baja. Plus or minus an inch had no effect. 21 Renegade was a good all round prop with the 100.

[brocluno]

OK, I have numbers for the motor: 140843C J003320

Don't know what they mean? Any help ...

[phillnjack]

those numbers mean its a 1978 140hp
so you now know the year of the engine for sure.

was this taken from the powerhead or from the bracket on the side ?
if the bracket, then look on top of the engine for a disc about 1 inch diameter and check those numbers too.
if they match up you definitely have the year 78 140hp rude .
here is a link to some parts and diagrams.
http://www.boats.net/parts/search/BR...43C/parts.html

hope this helps

[brocluno]

Yah, that helps, thanks