2004 engine?

2003

Ok, this past weekend I did not get a lot accomplished, but here it is...

Cleaning the heads to be send out for AFR CNC, they had a lot of carbon in the cyclinders


The throttle body was a bear to take apart, ended up having to drill out the screws. I know this will come back to be a problem later on.


The upper and lower intake ready to out out to be boiled.


A view inside the intake, lots of oil from the valve cover breathers and PCV. I may try and switch to a catch can instead.


And my new rear plate for the ECU, relays, coils, etc. This is the style on the new 525's. Will definitely clean up the mess at the back of the engine a bit

very nice. I hope the new TB plate screws are not to much trouble... but that could be a BAD problem if they back out later.

I would also pressure check your exhaust manifolds,,,,,my guess is you have a leak

Ok, now that I have my Sandy rebuilding under control, back to engine rebuilding...

Here are some updated pics of the heads back from Teague / Air Flor Reserach with the larger valves, new springs, retainers, etc. and the CNC porting job. They also fixed up some of the saltwater damage to the aluminum on the exhaust flange.

The block is also back from the machine shop with a clean bill of health (the 150 missing HP is still a ghost) and the new camshaft installed. I've got the carbon fiber valve covers, head gaskets and other goodies on order. This weekends order of business is media blasting the intake and pulleys to prep for paint.

what was your engine oil temp in that engine? In once had one 525 running higher temps than 2 other that was also 500-600 rpm lower than the other... came out great after rebuilt but never found any real problem before either...

I want to say one ran a little hotter than the other, but not much, maybe 10-20 degrees and I don't recall which was which. I also had all the injectors rebuilt and blueprinted. They said they were all in decent shape for their age (10 years) but now they will all be like new.

I would swap the p/s pump over and run the engines reverse from where you had them before. See if the other one does it after rebuilds. Maybe it is a boat bottom issue that developed over time? I know it is a long shot.

Also, did someone monitor the timing on the "slow" engine? You could have a low fuel volume issue that is enough for the knock sensor to cue a reduction in timing, but still enough fuel to run the boat at a reduced power level.