[glenn maerki]

FINALLY!!!! Just got back from a 40 mile run with the fleetguard restore plus and with the new 180 deg. t stat. Engine came up to temp with a little overshoot to about 185 deg, i could see the temp drop off when the t stat opened and for 40 miles at 2400 rpm the temp sat at 181-182 degrees. no creep. must have been that t stat all along.

1 user thanked author for this post.

Hunter Begnaud

[glenn maerki]

I put brand new cork gaskets on the strainer lids this spring. Typically do not grease the lids but that might be a good idea?? i do run baskets as well as the south bay strainers. I’ve never seen anything in the baskets in 21 years of running this boat. You think I should run without them? as I mentioned the impellers are both new. Would be surprised if it went bad already… really have no time on it since I’ve been chasing this problem. pumps aren’t bad as far as access…the tight area i was referring to is where the oil cooler is. I could pull the pump and recheck the impeller or maybe just swap pumps..??

[glenn maerki]

I’ll give you a rundown of what I’ve done on the SW side:
dove under the boat to ensure the south bay strainer screen was clean. It was. i remove them every year, wire wheel them clean and put a coat of pettit barnacle barrier on them. pulled the hose off the thru hull and opened the valve…that was clean. removed the feed hose from the strainer to the SW pump- hose was clear. my salt water feed hoses are wire reinforced and show no signs of collapsing. SW pump has a brand new impeller. Pipe and 2 elbow hoses that feed SW from the pump to the oil cooler….checked and clear. No leaks at either hose. Ran rydlyme through the sw system to clean any growth. both the oil cooler and the heat exc. look reasonbly clean. I also used a wooden dowel to “rod” out the oil cooler and heat exc. found no tubes clogged. I don’t think there’s anything left on the sw side to rule out. As you well know, the SW cooling system on these engines is as basic as it gets. I’ve attached a couple pics…strainer hose, coolant recovery bottle and the oil cooler as best I could get….very tight in there to get pics.

[glenn maerki]

I’m getting ready to descale the freshwater side with Fleetguard Restore Plus. Decided to swap out the t-stat as its about the only thing I haven’t addressed. When I pulled the 160 deg. stat out, i noticed it has scoring almost all the way around. I attached a picture. You’ll need to zoom in to see the scoring. No idea if that would prevent the t stat from opening far enough to allow sufficient coolant flow. Will run it tomorrow with restore plus and then go through the flush process. will see what temp it runs at with the 180 deg stat in. any thoughts on the scoring and possible affect on cooling? Appreciate the help. I’ve spent far too long searching for the issue….

[glenn maerki]

thanks for the quick reply Tony. I haven’t upgraded the turbo coolant line but the stbd engine has the same setup and no temp issues on that engine. I pulled the elbow from the head and its wide open….no blockage at all. seawater pump may be 6-7 years old and I just put a new impeller in. both engines had new pumps installed at the same time. I also just descaled the SW side with Rydlyme as part of this issue. also push a rod through the tubes on the oil cooler and no blockage. none of this makes any sense.

I’m thinking of descaling the freshwater side again (Fleetguard restore plus) ….that hasn’t been done for about 6 years or so but both engines have always had the same maintenance protocol. the stbd runs at 165 all day long no matter what the load/rpm.

what is your thought on running without a t stat?

[glenn maerki]

so I’ve been through the entire cooling system at this point and still have same issue of temperature creep when running higher load/rpm. The only thing I haven’t ruled out is the thermostat. I bought the 160 deg. stats from Seaboard maybe 3 years ago and have limited time on the engine since. Two questions:

1. I’m thinking of pulling the thermostat and running the engine without one. Are there any concerns with doing that?

2. Tony – have you had any issues with the 160 t-stats. I’m just guessing that maybe its not opening enough and restricting coolant flow?

at this point, I’m out of ideas and really don’t want to start throwing parts at it. Appreciate any input. Thank you!

[glenn maerki]

That’s an interesting thought…..debris in the intake hose. Hadn’t considered that and easy enough to flush out. Upgrading the coolant system is not the problem though….both engines had adequate cooling systems and the stbd is running perfectly with the same system. Don’t disagree that upgrades are better….but something is wrong. That’s what I want to identify and fix.

[glenn maerki]

I removed the elbow that feeds the turbo and it is clean. Used a borescope to look inside the head (can only get in a short way) but I don’t see any buildup/blockage whatsoever. There’s clearly no restriction there. I do have a spare freshwater pump and am thinking of throwing it on as I have the coolant drained. Has anyone ever had one of those pumps go bad?

[glenn maerki]

thought i had the leak problem solved but running for about an hour with an oil absorbent pad under the pump I would estimate maybe a half an ounce or so stain on the absorbent pad. So I pulled the pump again and replaced all the banjo bolts and crush washers. Just took another ride and still leaking but I have no idea where from. On top of that, I now have an idle roll of 100-125 RPM at low idle and higher idle(1300 RPM). This BTW is the same engine I’m having temperature creep on. So 2 more questions:

1. what would cause the idle roll?
2. suggestions on how to deal with the inj. pump leak. I’m out of ideas.the leak is small enough where you cant find the source but its still a fuel leak.

thanks in advance for your input

[glenn maerki]

so Tony, the elbow into the block should be 3/4 NPT X 1 ” hose barb correct? the new banjo is 1″ hose..?

[glenn maerki]

gonna switch port and starboard caps and see if there is a change

[glenn maerki]

any thoughts on why that engine is pushing coolant into the overflow tank and not pulling it back in when it cools down?

[glenn maerki]

thanks Tony

[glenn maerki]

there are crush washers on the banjo bolt. all were replaced when the pump was rebuilt

[glenn maerki]

I tried to delete my previous post but apparently cannot do that. Anyway, I used paper towels to isolate and then recorded short video of the location on engine start. Would like to try to fix without removing the pump but not sure I can do that……

[glenn maerki]

used a GoPro to get a video of the leak. the drip you see to the right in the video is coming off the tube at the 6 O’clock position (bottom of the pump). the drip on the left side is coming off the port at the 8 O’clock position. Hard to get a video of the port at 10 o’clock because of restricted access. not sure if the leak on the left side (8 o’clock position) on the pump actually starts higher….maybe the 10 o’clock port. I have a lot of video and i dont see anything from above the pump (i.e. fuel supply lines) so it must be the pump…???

any ideas?

[glenn maerki]

Hey Tony

Have the boat running now and seems to be running well with one exception. seems I have a small coolant leak at one of the head bolts. It’s small and I’m not using much coolant but want to fix that. Big concern obviously is head gasket… but hoping a retorque of the head will take care of it. Just wondering what your procedure is for re-torqueing the head. Do you loosen all head bolts and then torque in recommended sequence or loosen 1 bolt at a time and retorque?

Not sure if you had a chance to look at the pics I sent but would like to hear your thoughts on freshwater coolant system and turbo failures……

Thanks

Glenn

[glenn maerki]

not sure Rob. to be honest I always close the seacocks when I open them. My guess is the caps are very close to the LWL.

[glenn maerki]

title of the photo should give you some info of which engine and

[glenn maerki]

I’ve tried to get shots that will give you a feel for the set up. Its difficult to get better shots as the access is tight.

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