Early signs of leaky headers 525s
 

525/700 owners- what are some of the early signs to look for on these Engines with Original Headers?
I understand in 09, these CMIs were "Supposivlely" improved!
Scarey thought worrying about Leaky headers and loosing an Engine!!
Having them Pressure tested each season and/or sending them back to CMI to be Refurbished would also be an option!!
Thoughts?

Best I've heard and read many a thread is pressure checking constantly.

If you see any steam coming from the exhaust or hear any sizzling sounds upon shutdown they're probably already leaking . Pressure test .

Early signs are a lot of steam and when they get real bad it will hydrolock the motor. If you pull the plugs you will see traces of rust from water inhilation..my advise is to junk the headers..unless you have more patience than I do...I am not a big fan of those headers and I have sent them back many many times and they don't last..If you want to do it right get yourself a set of stainless marines.they are lighter in weight and they make more power on a dyno..I have tested them ..

This guy is my mechanic. My headers leaked 3 times causing two top end rebuilds. He wouldn't re install the junk CMIs after the 3rd time(probably saving me $$ and headaches) so I went with the Stainless Marine set up. 2 years with no problems. I had them painted blue to match the motor. They look great.

Signs of leaking are steam, hard starting, feeling like its only running on 6-7 cylinders...

A vary bad sign is a connecting rod and pieces of a piston laying in the bilge..

Drain your headers after every time out.

Any pics of the engine bay with the blue manifolds??

+1

Not on this phone. I'll get some though.

+1,

I'd love to see those dyno sheets. . . . . . . .

You should be looking deeper for the cause. Mine are on their 7th season with no problems.

Hours, salt water and a bunch of other things play a part. Mine started to fail around 200 hours which is pretty common for a boat used mostly in salt water.

Yes, big difference with salt. Flexing seems to be an issue too.

All that wonderful extra ethanol kills headers faster that in that past also...

A buddy of mine had a new 39 Cigarette w 525's. His early tell tale signs of headers failing were high oil temps. The water would get past the rings and make its way into the oil filter causing it to by pass (filter & cooler) driving oil temps way up.

High oil temps were the first sign on mine and also on a friends 38TG.

Last year, I had leaks in two sets of headers; one of which cost me an engine. Looking back, I now recall my oil temps being pretty high but I was new to those motors and I thought that was the normal operating range. My current 525's rarely get above 150*, the ones in my old boat consistently ran above 200.

I've posted this already about 100 times, but the way to keep up these headers, ESPECIALLY in salt water is to flush them religiously, EVERY time you run the motor, no matter what. And I drain them once they cool down. I also pressure check them every 10-15 hours with an air compressor and a leakdown tester (ie: drain them, fill them with compressed air and see if they lose pressure).. You can do this safely with the headers attached to the engine. Don't do this with water while attached to engine because if you do have leaks, you will force water into the cylinders..

Mine too but looks like we're both in fresh water.

My headers are 9 seasons old, boat has never been in salt water, used in Wisconsin and Ohio so season is short. Consider myself lucky and keeping an eye on them.

So how many hours are on them?

I have 325 hrs on my headers, all freshwater after the first year the boat spent in Fla.

Up here on the fresh water lakes in Maine, we don't see many header failure problems. My old Top Gun had 600 hrs on the headers with no issues, sold it to a friend who has used it only in salt and the headers have failed.

Also wondering if shore power connected and salt water use could be something to think about. If the shore power was connected, could it speed up the corrosion process?

E-Tops seem to fare better than the swept-tubes.

I had always heard the first sign of a CMI failing is when it comes out of the box.... :party-smiley-004:

:eekdrop::lolhit::boat: