cleaning my cross flow v4 cooling system, Multiple questions!

[bscappell]

Cleaning my cooling system after getting over heat issues. Here is how I got here:

here is what the cooling passages look like:










Question 1: how much of this should I clean out? I assume I need to be super careful about not getting this into the cylinders? I read using a shop vac would help along with towels in the cylinders?

Question 2: the deflector hoses were pretty nasty so those are getting replaced as well. do those just get pushed straight in where the old ones were? no fitting that goes into the other end?

I will be using heads off of a previous (freshwater) motor so the gunk in the current heads (plus a broken bolt) won't be an issue.


I noticed there are 2 ports on the bottom of the powerhead that mate up with the mid unit. I believe that they are part of the cooling system (shot water into an old powerhead I had to see what they did) but it doesn't appear that the diagram from this thread shows them as having a purpose?

Question 3: Any idea what purpose they serve?

here are pictures of what I am talking about:

mid unit



bottom of powerhead (this is a different powerhead as the one in question is on the motor currently)



H20 flow diagram (credit to interalian)




The reason I ask is when I did a powerhead swap, I noticed one of the passages (the circled one on the bottom of the power head) was clogged with sediment. I tried picking as much out and had a marine shop look at it to see if it need to be fully cleaned and they said "it should be fine".... yeah pretty reassuring. wondering, thinking, is this the issue with my overheating problem altogether?

what else am i missing?

 

[racerone]

The deflectors just get pushed into the water jacket.------There is no fitting on the other end.-----Note----- they are hose material but water does not go through these deflectors.

 

[bscappell]

The deflectors just get pushed into the water jacket.------There is no fitting on the other end.-----Note----- they are hose material but water does not go through these deflectors.

OK. I wondered that. Makes more sense. Thank you Anyone answer the other questions?

 

[emdsapmgr]

Here is a pic of a fresh block with the a "normal" deflector to the left, and a mis-placed deflector on the lower right.

 

[interalian]

I wouldn't go nuts trying to scrape out every bit of scale/salt. The factory primed the interior passageways, probably for a good reason, and it's probably best to not damage that red coating. Loose stuff and larger flakes sure, but no need to scrape it right down to metal. Will you be running it in fresh or salt once it's back together? And any salt bits that end up in the cylinders, just wipe away with an oily rag.

Also, looks to me like your major problem is the choked water passage next to the center deflector in this photo.

 

[bscappell]

she will be in a freshwater home from now on. I see how the center deflector is to be seated but does anyone have a picture of how the bottom deflector should be seated as well?

 

[interalian]

Bottom deflector goes between the indent in the bottom of the water jacket and the cylinder head boss just adjacent to it. Note: if you look under the bottom cylinder, you can see the oval port where the water feeds under pressure from the center of the block water jacket. In the picture in post #5, the water comes toward you beneath the lower cylinder, then flows counter-clockwise around the cylinders. The two oval holes in the head gasket align to the area next to the red fuse holder.

 

[bscappell]

Bottom deflector goes between the indent in the bottom of the water jacket and the cylinder head boss just adjacent to it. Note: if you look under the bottom cylinder, you can see the oval port where the water feeds under pressure from the center of the block water jacket. In the picture in post #5, the water comes toward you beneath the lower cylinder, then flows counter-clockwise around the cylinders. The two oval holes in the head gasket align to the area next to the red fuse holder.

got it, thanks! got my service manual out and found the water flow diagram in there as well. I got a package from Iboats today so I will be putting the heads back and torque in proper order in the morning. I will let everyone know how it goes!

 

[bscappell]

Got everything put back together. Still runs hot. takes more time to get up there BUT the starboard side head was running up in the 190's degrees. So i pulled the thermostat hoses (as was suggested by member Fed) and low and behold the temp dropped. so sounds like i need to pull apart the thermostats and check them?

Also noticed water coming out of a spot that doesn't seem normal:

<iframe width="560" height="315" src="https://www.youtube.com/embed/CYvN5k0N0kY" frameborder="0" allowfullscreen></iframe>

thoughts? doesn't seem to be coming from the head area (meaning a leak from where i was just doing work) could it be related to question 3 i had in the original post? I never did get an answer on that.

 

[bscappell]

Correct YouTube link: https://youtu.be/CYvN5k0N0kY

I also thought I would mention WHY I didn't head advice from 15 days ago (and ruined most my salmon fishing season). As you know the Thermostats are not part of the powerhead. they seemed to be operating fine before swapping powerheads so I thought, no need to check that. I was wrong. But i wonder if maybe its not that the stats are bad but clogged because of the salty state of this powerhead? i guess i will know once i get into it......

 

[interalian]

Bleed holes could be clogged in the thermostat plate. If blocked, water won't flow in and past to heat the thermostat, so it stays cold and closed. And since you had a lot of salt flakes, it would be easy for one of them to plug the bleed hole.

 

[bscappell]

Bleed holes could be clogged in the thermostat plate. If blocked, water won't flow in and past to heat the thermostat, so it stays cold and closed. And since you had a lot of salt flakes, it would be easy for one of them to plug the bleed hole.

that's what i was thinking. I will get in there tomorrow! any idea on the water in the video. I can't remember if thats normal or not.....

 

[bscappell]

thermostats were indeed dirty. bleed holes clogged as well. lots of rock salt ha! runs MUCH COOLER now!!!! thanks all

 

[interalian]

Good news, glad you got it. Happy boating!