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air shroud for 540

if you hit the word search above these posts and type in the word shrouds it will bring up a list and one of them is for 540 shrouds and it is complete with pictures
This guy makes a great shroud Robert Anderson 772/633/2450 he lives in vero beach tell him Terry told you to call .
Picked mine up for the new motor from Robert yesterday.

I've seen alot of different shrouds/cowlings out there & I must say Robert's appeared to figure out all the problems from the past.

He molds in (2) two supports across the top of the shroud for strength & also provide the mounting hardware & cover plates for the cylinder barrels.

I had to do a little sanding/cutting for it to fit properly which was to be expected.

Tomorrow night we're taking her out on her mayden voyage & running her w/o the shroud to give us a baseline temp.

Tuesday we'll run her with the shroud on with the same weight & see what the temp drops to.

Everyone who runs runs says I can look @ a 30-40 degree difference in temp & that it will lengthen the service life of the engine.

I'll provide specs after both runs.
Longer life for the engine, and you'll probably notice it's quieter too.

Lookin forward to the results.
Olf Art":2suq34jy said:
Longer life for the engine, and you'll probably notice it's quieter too.

I could believe how quiet the engine is now!!!

Yellow tagged crank, (0) zero gram matched pistons & (3) three gram matched rods.

You can still stand next to it @ 1200 rpm & have a normal conversation.

I sure Robert's shroud will be the icing on the cake to Super Dave's engine.
mwood7800":3une0qb1 said:
what about checking oil and changing plugs with a shroud, do you have to remove it?

There is a hole in the shroud to check the oil.

Checking plugs is also not a problem.

I am a little confused about why you would need a shroud. Those CHT's are really low. In fact I would be a little skeptical about them. I don't know what kind of boat you are running or what is on it. To answer your question to change to top plugs shroud has to come off.
Not on the one Robert makes.

Plenty of room to change the plugs.

It's off the boat right now.

After the paint job I'll take some pic's & post.
Don't know about the upstack.

I know he's got molds for a staight/angle valve 0540, 0470 & 220.

Give him a call @ the number above.
Maiden Voyage - No Engine Shroud

08/21/06 1800hrs Temp 84 degrees

20 gallons of fuel & normal gear (tool kit-safety gear-extra oil)

Had my buddy on board who weighed in @ 200lbs.

First was a (4) four mile run through the shallow marsh (including a (100) hundred yard dry run just prior to shutting down), max RPM @ one point was 2500.

As hard as I tried, I couldn't get the oil temp to run over 125 degrees!!! :shock:

Headed for the deeper water of Lake Washington & ran from the east shoreline to the west & then turned back on the same route.

Oil temp never got above 140 degrees :shock:

I burned (5) five gallons of fuel during the run.

At the end of the run (approx 1hr 20min) by buddy looked @ me & said, "Are you sure you needed the shroud?" :p

Update on Wednesday after I install the shroud & run under the same conditions.

Note: My old 220 would have burned (10) ten gallons of fuel & ran near 200 degrees.
Yes Robert can build you a upstack shroud . All I will say is I would rather spend the money for a shroud than rebuilding a motor
That is exactly my thought because this is a super charge motor. I've been told you got to watch it because the can get hot in a hurry.

Thursday, 08/31/06


The bank @ LK Washington/Wickham said it was 82 degrees.

Launched @ 2300hrs.

Had myself, a mate & a client on board for a total of 660 lbs.

Fuel was topped off @ 36 gallons.

Had normal gear plus, small cooler, throw-over bag, harpoons & crossbow.

During the run out across the lake the oil temp maxed out @ 130 degrees running @ 2200 rpm.

Once I hit the marsh the temp cooled to 110 & stayed there.

Got stuck once on a tussut & temp maxed out over a (5) five minute period @ 150 degrees while pushing 2800 rpm's.

@ the end of the hunt (0430) we had (2) two gators in the boat, an (8) eight & fatty (10) ten footer.

We were (1) one mile south of the Oakhead when we packed it in & jumped up on plane for the run back. (which took place on the river run in deep water).

Only came off of it once while crossing the weir.

Temp never broke 130 degrees & we burned (20) twenty gallons of fuel during the hunt.

I'm sold on the shroud.

Thanks Super Dave for a great running engine!!!
hmgm123":2qlqauml said:
Seems to me Capt Jeff according to your info you did better without a shroud. :shock:

Well let's jsut look @ the numbers with the shroud?

200lb extra person
100lb additional fuel
100lb additional gear
450lb in gators
850 extra pounds

6hrs additional run time

Shallow water running: 110 degrees (with shroud) vs 125 degrees (no shroud)
Deep water running: 130 degrees (with shroud & extra lbs) vs 140 degrees (no shroud)

It looks to me like the numbers show the shroud did its job. :D
If thats your oil temp you might need to check your vernatherm, I would be afraid to get above idle with my lawn mower if that cool.