Carver Owners Forum

I took the boat out this past weekend and still have a problem with the starboard engine running hotter than the port. I used a temp gun to get some readings. The starboard thermostat is running about 173 with the temp gun. The port is 165 to 168. The exhaust manifolds are 170 at the back and runs up to 210 at the front. The port engine shows about 160 up to 190.

Another post shows the steps I have taken. viewtopic.php?f=8&t=3764

1) when I winterized the 5 gallon jug I was pulling the antifreeze through took a lot longer to pull through the engine than the port engine did,
2) I treated the engine with Ridlyme and it improved the flow. Still slower than the port engine but thought it would buy me some time.
3) the boat is 13 years old. I went ahead and bought replacement heat exchangers, oil coolers, transmission coolers, and thermostats. I also am going to buy new hoses. Everything I read says that they are probably past their service life.

Questions are:

Are the temp gun readings out of line with “normal”?

Any recommendation on brand of hoses to use? Some will be bought formed, along with about 24 feet of 1” hose for some straight runs. I will probably use wired hose.

Any gotchas involving the heat exchanger to watch out for?

Should I replace the risers and manifolds? (All fresh water use)

If I replace the risers and manifolds, should I buy new nuts and bolts? What is the best stuff to coat bolts with prior to putting the nut on them.

Should all the clamps be replaced or just re-use the old?

Any other thoughts, advice, or suggestions?

Thanks in advance.

Maybe it's not the cooling system?
Timing ok?
Fuel delivery ok?

waybomb wrote:Source of the post Maybe it's not the cooling system?
Timing ok?
Fuel delivery ok?

Timing is good. Had a problem with fuel two years ago. That was water in the fuel filter. Changed out and fixed it. Remember that the engine isn’t pulling water through the system as quickly as the port engine.

I pulled one hose at a time prior to the Ridlyme treatment. The water was constricted going to the exhaust manifold out of the heat exchanger indicating an issue with it. The problem is that the exhaust hoses are tight against the HE sides so I will have to pull to look inside anyway.

If your sure both raw water impellers and raw water pumps are in A-1 Shape, I would run another RydLyme batch I her and let it sit. Your only talking 8 degrees difference between the two motors. Are you getting more steam out of the starboard engine than the port? Maybe Start with 2 new thermostats. I'm assuming by the temp readings this is a closed cooling system. Another thing, if your going to run this puppy south into salt water, I wouldn't be in a real big hurry changing out all them expensive hard parts until after the salt water run, unless you feel they are about to fail for sure.

Nharrison5 wrote:

waybomb wrote:Source of the post Maybe it's not the cooling system?
Timing ok?
Fuel delivery ok?

Timing is good. Had a problem with fuel two years ago. That was water in the fuel filter. Changed out and fixed it. Remember that the engine isn’t pulling water through the system as quickly as the port engine.

I pulled one hose at a time prior to the Ridlyme treatment. The water was constricted going to the exhaust manifold out of the heat exchanger indicating an issue with it. The problem is that the exhaust hoses are tight against the HE sides so I will have to pull to look inside anyway.

Based on this you may have found the problem, remove that thing and have it flushed and pressure tested.

To me the temps you got with the Ir gun did not seem outrageous, you will never get both exactly the same.....to be reasonably accurate with the gun you have to shoot the same spot on each and have the gun close to the spot you want to check.

keep us posted.

OK, Two more questions.

I have ordered new hoses for both freshwater and raw water cooling systems. The pre-formed hoses from Marine Parts Source came in without wire in them, have the Crusader part number on them, but do not appear to be J2006r2 compliant. the bulk hose is Flex Shield 250 J2006R2 compliant and does have the wire in it. For those who have replaced hoses, do you just order using the part numbers and get the non-wired hose, or do you "make your own" with the wired version?

Second question. It appears that Dex Cool is the antifreeze recommended by Crusader in the manual (pink in color which is what appears to be in the engine now). The top off stuff that has been with the boat since I bought it three years ago is Prestone 50/50 Pre-diluted Antifreeze. I plan to use DexCool but have read about issues with seals and gaskets. My Crusaders are 2006 engines. The Dexcool is what you are supposed to use in GM engines. What type of AF do you use and why?

I believe the DEX cool is used in most all GM applications from about 1997 to current.

Well, I got the oil cooler changed, and changed out three hoses. I have three more hoses to finish the raw water side. The transmission cooler is against the wall and will be difficult to get to. I would like to get that changed before I change out the Heat exchanger. I will get this side done over the next two to three weeks, and then wait until later in July for the other side.

A couple of things I learned. Getting the oil cooler out and replaced was a 12 hour affair for me. Tight and up under the engine made it difficult to get the leverage necessary to break the oil hoses attached to the 90 degree fittings loose. I had to order two new 90 degree fittings because the old ones were frozen on. After completing the hoses and the oil cooler, I will have to wait until after Memorial Day to change out the Transmission cooler and the HE.

Here is the Transmission cooler. I can’t tell much without the other hose removed and ran out of time to try to do that. Anyhow, some progress, but slow going.

From the picture it looks like at least half of your raw water passes are clogged. I am not sure what water you boat in, but it seems a good long flush with barnacle buster or something similar would clean this up for less $$ and time than replacing all the exchangers.

Yes, your picture shows the problem, another RyLime treatment is in order with maybe a higher concentration mixture or full strength. My open cooled system wasn't over heating but producing steam. RydLime treatment cleared it up and plan on doing another treatment this season.