Drain it from the front, it's easier.

How to Burp Your Engine (Reply #6) [url]http://c34.org/bbs/index.php/topic,4518.msg26462.html#msg26462[/url]

Your engine will be slightly different, but it's the concept that should apply. You don't have to get all of it out.

It's not too difficult, but remember to ensure all the coolant from the expansion tank in the port side locker is empty too. Also, you won't get all the coolant out of the exchanger since it sits low at the back of the engine so have some containers ready to pour it into.

The petcock on the heat exchanger might take care of the last bit of coolant. Catch as much as you care to. Removing the zinc should take care of the majority of the raw water. Again, catch as much as you care to. Loosen then remove the radiator cap and you might get more from the petcock or front hose.

Been there done that David! There is a plug in the Kubota (M35) block on the port side that will drain the coolant. (Not near the boat or I would take a pic).

I also had the brazed on brackets break. Universal sells clamp-around style brackets which I fitted (really hard to hold the clamps closed to screw in the bolts though!!!

I struggled (a lot) with those clamps just this week, putting a few dings in the paint job I just lavished on the heat exchanger as I bumped into the transmission, etc. What finally worked for me was to tie wrap the clamp ends closed enough to get the bolt to pass through along with some threads to start the bolt. Got a few turns on each bolt, then snipped the tie wraps, then evenly homed down.

[QUOTE=HowLin;22108]

1. There is a plug in the Kubota (M35) block on the port side that will drain the coolant. (Not near the boat or I would take a pic).

2. I also had the brazed on brackets break. Universal sells clamp-around style brackets which I fitted (really hard to hold the clamps closed to screw in the bolts though!!![/QUOTE]

1. Howard's right. However, in previous discussions on this topic, I suggested -that the engine mounted petcock [B][I]may [/I][/B]not be the most advantageous place to drain the fluid. Actually, what I said was more like it's a stupid idea, but... The reason, skippers, is that petcocks are very small openings, and subject to getting clogged, and then, like the pressure relief valves on our water heaters, inoperable thereafter. The response from some was "It worked for me" and "Not a problem." I personally and, as an HVAC systems engineer, wouldn't trust it. Besides, as I posted then, the location is far from optimal to do it without drips.

2. There are two styles of HX: brackets and hose clamps. We have the latter and, with the right sized hose clamps, have never had an issue mounting the HX. Both the brazed on brackets and the bracket used to hold the hose clamps on are known to have failed. Check your engine while it's running on a regular basis.

Good luck, it's a doable issue that we've all faced and resolved.

Mine had one bracket off when we bought the boat in 2009. The amount of brazing material holding it on was pretty much nil. I had a rad shop rebuild it and they brazed it back on and re-did the other one as a precaution. So far so good. I think it was just poorly done originally. Time will tell.

I am like Bud. Had a bracket come loose over 5 years ago. I took it off and re silver soldered it. Has been on ever sense. There was just not enough on the first time.

[QUOTE=FlyMeAway;22141]

The only issue is, only 450 hours before it breaks? Is there something about our engines over-vibrating? Should I have that checked by a competent mechanic?[/QUOTE]

My bracket broke at 2700 engine hours. Stuff happens and no "competent" mechanic would ever give you an estimate of when something would break. If he did I wouldn't call him "competent." Just keep checking your engine when it's running on a regular basis. When my bracket broke, I only discovered it because the coolant started leaking. The hoses held it in place and the bracket was underneath the HX, impossible to see the break. I did everything else first: changes hoses, checked connections, you name it. Finally took the HX off and found the break, which had gouged into the shell.

Stuff happens. :eek: