Official Caterpillar3116/3126 Thread

yea, just a drain. Dry it all up and make sure it’s actually coming from there though. We had a leaking J hose that was slowly running down to that point and could’ve easily been mistaken for a leaking drain plug, since it’s the lowest point it all runs to there

 

Yeah I was wondering about that, since it's a low point, I'll check it out.

 

Probably one of those clamps above I'd imagine. Once it cools down, they typically leak. Usually one turn or so and they will tighten up.

 

Changed the zincs out this weekend.

I'm wondering if there is a grounding problem on the transmission oil cooler.



PORT IS ON THE LEFT - STBD IS ON THE RIGHT

The cooler is attached by the raw water hoses and the brackets that hold the tank

I've got a good bit of paint on there.

Maybe hit it with an OHMS meter, or maybe y'all will tell me I don't have a problem.

Also - despite these looking so good, the aftercooler zincs were let go far too long.

Will pull them at 3 months to check and likely end up at a 6 month schedule.

Also a wake up call for me to get the fresh water flushing system going.

I used to run 18 months on my Yanmars, where I flushed the engines, genny and HVAC after each use.

BEST !

RWS

 

Too many zinc anodes in the oil cooler - should be one each. Assuming your boat's bonding system is in good health, use that (the hull zinc) to gauge the zinc life for the others. For example you replace the hull zinc once a year and it is half consumed then you should see close the same on the gear cooler and engine / HX zincs. Things that have their own anodes should not be bonded to the hull zinc (green bonding wires).

 

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I was thinking the transmission cooler may not be bonded to the engine.

There's no wire for it.

RWS

 

It's probably grounded with the engine and battery negative simply because they are bolted together but neither the engine nor the coolers nor the exhaust riser should be bonded to the hull anode; they have their own anodes.
There's a difference between grounding and bonding.

 

not suggesting any connection to the bonding system

There's no provision for a bonding wire from the gear cooler to the block.

likely I have too much paint/primer on the transmission cooler and the bracket

 

I don't get the "bonding wire from the gear cooler to the block"..... Are you saying the cooler and engine block needs to be at the same electrical potential - grounded together?
Those things could be separately mounted or bolted together for that matter - it makes no difference with respect to the anodes installed other than all of the anodes need to be evaluated as a system.
This is how it works - consider one metal attached to another one more noble than the other and both are in contact with an electrolyte (seawater). You have a galvanic battery of sorts. The less noble metal will galvanically give up its ions first rather than eroding the more noble metal. So, on a gear cooler that is constructed of bronze and copper and has a zinc alloy anode in electrical contact through a brass fitting. The zinc is considerably down on the noble metals chart and will be the sacrificial metal. Nothing else is needed. Electrons will flow everywhere and if several zinc's are in the same electrical path then erosion will be shared.

 

With respect to your picture of the zincs - first the gear coolers are over "zinc'd" and in one case there seem to be inadequate electrical conductivity between the zinc and gear cooler. So, put only one anode in each cooler and thread them in dry. Secondly, you don't allude the condition of the hull zinc (or any other for that matter) to determine if the cooler zincs were ready to change. The idea is you would like the boat's anode system to wear equally.
With that said if one cooler has good electrical contact with the engine and the other does not then the zincs will erode differently as they are playing with the other raw water filled metals. What I'm trying to say is that it's a system and it needs to be evaluated as such.

 

All good thoughts.

With no threaded connection between the gear cooler & block, I suspect too much paint is not allowing for conductivity.

Will pop those brackets this weekend and take a drill mounted wire brush to the back side of the bracket and the cooler to make for better contact.

Tom, I did take your advice and used Loctite 234194 Copper LB 8008 C5-A Anti-Seize Lubricant ONLY at the cap threads.

Most all the zincs were good, however the aftercooler and bottom zincs in the HEX were nearly gone.

I was really surprised at the differences

Will wrap up the install of the fresh water flush this month.

The last 30 seconds or so is where I add the SALT AWAY product.

BEST !

RWS

 

You should be good with the Loctite as it is conductive or assemble dry; I use the Loctite also. The key is look at all of the port engine zincs then look at all of the starboard engine zincs. Then look at the hull zinc. The raw water flow through the engines is separate and the zincs in each of those flows tell a story on how well each of those engine's components are protected. Remember also that an engine can have stray current from an electrical fault and take out those zincs faster than others. Same goes for the hull zinc on other stray current or a structure near the boat leaking current. I agree that getting both the gear coolers either well grounded to the engine or well insulated from the engine will help level the playing field to determine that the engines are adequately protected. Same goes for all the other components bolted to the engine. Conversely to all of that if the zincs are not being eroded then there are other issues that can also have dire consequences.

 

Dancer I think your zincs look pretty good. West coast of Fla I would think is more salty than the brackish north Chesapeake bay and my zincs always look far more worn than yours after a season. I would clean and re install if mine looked that good. Would think your aftercooler and hx zincs are about the same.
As I recall CAT recommends locktite on the shoulder of the zinc to plug and thread sealer on the plug. A ohm meter will show no restistance from the plug to ground with any sealer I have ever used. Bigest reason to check zincs is to not have one swell and stick in the engine which then needs acid to remove.
Fresh water rinses never hurt either.

 

Interestingly, the aftercooler zincs were past due as were the bottom HEX zincs.

 

So as part of my winter layup, the marina inspected my 1998 400 Sedan Bridge and recommended that the alternator belts be changed. I purchased the belts from Cat per my 3116 engine serial numbers.

The marina just called me and said that they cannot quickly change the belts. There is a second set of belts in front that needs to be removed also PLUS a cover and a coolant pipe. They are saying it will take two days and about $3 Boat Bucks to get this done.... Is this crazy or what it would cost? Should I find another mechanic to come in after the boat launches and I am not tied down to the marina (Skipper Bud's) staff?

 

If I remember correctly the outer belt is for the alternator and inner one is for the engine coolant pump.
To change either the synchronizer cable must be removed and it needs to be aligned when going back together. If you are down that far, change the inner belt idler pulley which is also part of that belt's tensioner. I seem to remember also that a bracket needs to be removed to get the inner belt off. All in all though it's not that big of a job. 2 hours for a mechanic that has done it before.

 

Thanks Tom. They are saying the belt order is opposite with the alternator inside. They did say a bracket but they made it sound like a cover.
It's the 15 hours of labor that has me going...

 

That small pulley is the engine coolant pump - inner belt.

 

Unless there's a huge design change between the 3126 & the 3116 that is frig'n nuts !!! Mine was more like 2 hours per engine.

 

and from what I've read a weak point on these engines? I'm not sure if that's referring to the belt itself or the pump but I know I've read of pump failures causing rapid overheat