OUTLAW EAGLE MANUFACTURING

ALL IN · Joined: 30 Jul 2007 Posts: 11

Appears to be allot of CX boats blowing engines apparently mostly piston problems, any suggestions on why or how to alleviate the problem

RPM · Joined: 17 Dec 2006 Posts: 189 Location: Nechako

guess you can rattle the pistons out of anything if you want to push it up to the edge . lots of them are going the distance too , and know of one in perticular doing it on pump gas ....... i think they make pretty decent hp for the money , but they are only a cast rotator so don't push the tune-up too far and run it @ 58-6000 .

boosted · Joined: 04 Jun 2009 Posts: 378

The pistons in the ct engines are hyperutectic (hyper explosive). They will not tolerate any detonation whatsoever. They will also not tolerate any thermal shock loading. Every engine that has been sunk has blown a piston later. The valves are fairly soft and do wear alot but don't really seem to cause any major issues. The only other issue with them that I know of is that the oiling system can be a real bugger to get primed if not done properly.

With the ct engine you cannot run anymore than 28 deg timing on straight av gas or you will have issues at some point. If you are trying run pump your down at 26 or less.
You can get a stand alone knock control system for this engine. I have one on mine and it works flawlesly. I do have an extra one if anyone is interested. $750.00
If you have a motor that has been sunk just change all the pistons.
The ring gaps from the factory are extremely tight as well as piston clearances. .0005 on the pistons and around .012 on the rings give or take. This doesn't seem to be causing any issues because of the alum block but make sure you warm it up good before you drive it hard.

When priming the new engine if you don't have a priming system. Fill the oil line that comes out of the oil pump and hold it up while you rotate the engine backwards by hand. This removes any air from the oil pickup/oil pump/ oil line. Then put this line into a bucket and crank the engine until oil flows from the line into the bucked(only takes a couple of seconds). Then install the line and put the line that goes back into the engine into a bucket and crank the engine again until you have oil flow. Then hook up the lines and you should get oil pressure in only 5-10 sec cranking. Air in the system is like a spring. You can compress it and as soon as you remove the pressure it will start to expand. With the lines in the bucket there is no resistance so the air is pushed out quicker.

I have heard seen one blow up from a broken rod but it could have actually been the piston first. It was hard to tell. Other than that the only other exploded engines have been deto/thermal shock/install issues.

Hines · Joined: 05 Jul 2005 Posts: 304 Location: Red Deer

For oil pressure just spin the engine over with 3/8s drill (air) you will have no air issues at all.

boosted · Joined: 04 Jun 2009 Posts: 378

Hines · Joined: 05 Jul 2005 Posts: 304 Location: Red Deer

Sorry man do it all day long with 632 cu in engine in car, with plugs out . Just got back from mission won top sportsman class ran a 6.84 205 mph trophy is called a wally pretty cool.