CAT 3126 HEX

I contemplated removing the genny and restoring, but I was down for surgery for about 3 months. Not happening this year.

I did get a new dual stage muffler installed, so that helped the noise, but it still needs a tune up. It puts out great power, but vibration is a little harsh. Read in here somewhere that servicing the injectors and redoing the isolation pads helped as well. It needs a good cleanup, a few new pieces and parts and a paint job.
 
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dtfeld said:
I contemplated removing the genny and restoring, but I was down for surgery for about 3 months. Not happening this year.

I did get a new dual stage muffler installed, so that helped the noise, but it still needs a tune up. It puts out great power, but vibration is a little harsh. Read in here somewhere that servicing the injectors and redoing the isolation pads helped as well. It needs a good cleanup, a few new pieces and parts and a paint job.
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Dave, if you ever remove it to repaint it, consider painting it white to match the motors.
Previous owner of my boat had a brand new Westerbeke Genny installed 6 months before I bought the boat and it’s painted the same color as the motors. Looks pretty sharp.
I think the White is quicker to show any leaks or drips too which I think is good so you can get right on them.
 
dtfeld said:
I contemplated removing the genny and restoring, but I was down for surgery for about 3 months. Not happening this year.

I did get a new dual stage muffler installed, so that helped the noise, but it still needs a tune up. It puts out great power, but vibration is a little harsh. Read in here somewhere that servicing the injectors and redoing the isolation pads helped as well. It needs a good cleanup, a few new pieces and parts and a paint job.
Click to expand...
When you do your injectors, Frank W has a good shop he uses in TN - I think it's Dixie Diesel - he'll post it. They have done injectors for a couple of my dockmates in Chattanooga and everyone was pleased. I think they are in Columbia, TN.
 
Westerbeke service is always neglected but the head needs to be re-torqued and the injectors pop tested.

I’m sure there is a diesel service company in Atlanta but Carter is right. Dixie Diesel in Columbia Tenn. is superb. They are a licensed rebuilder for all diesel handling stuff like pumps and injectors and are a Cummins/Onan dealer as well. Pop testing is mounting the injectors in a test stand the pumping high pressure solvent thru them to test the pressures at which they open and close. If the test showed less that spec they will rebuild the injector. You only pay for testing and for any rebuilding needed. In my case, the testing fee was $50 and the solvent cleared the bad spray pattern so no rebuild was needed.

Dixie has done all my work for the last 25 years and they do great work and are honest. But like most specialty shops worth a darn, they are not free but are fair.
 
fwebster said:
Westerbeke service is always neglected but the head needs to be re-torqued and the injectors pop tested.

I’m sure there is a diesel service company in Atlanta but Carter is right. Dixie Diesel in Columbia Tenn. is superb. They are a licensed rebuilder for all diesel handling stuff like pumps and injectors and are a Cummins/Onan dealer as well. Pop testing is mounting the injectors in a test stand the pumping high pressure solvent thru them to test the pressures at which they open and close. If the test showed less that spec they will rebuild the injector. You only pay for testing and for any rebuilding needed. In my case, the testing fee was $50 and the solvent cleared the bad spray pattern so no rebuild was needed.

Dixie has done all my work for the last 25 years and they do great work and are honest. But like most specialty shops worth a darn, they are not free but are fair.
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Would the head retorque and injector service smooth it out? It’s not horrible, but would be an improvement, along with a sound shield. Could this be done in place or would it be best practice to pull the genny?

I’ve concentrated on getting the main engines and transmission coolers and cooling system back into top shape this winter. I’m leaning towards leaving the genny for next year. But if it’s something that could be done easily in place, I would consider doing it and taking it to Dixie Diesel based on the recommendation.

If it’s difficult to do in place I think pulling it and doing a proper refurbishment is the better course of action. But that will likely have to wait for next year. I want to have time to get it done right.
 
If you have worn injector orifices, carbon deposits on the tips, or a bad spray pattern, then definitely, cleaning and servicing the injectors as needed will help. If you have a 3 cylinder engine, then no service or even having the Pope bless it is going to smooth it out completely.

Tanking the injectors to a specialty shop 250 miles away is wasting time......3 injectors packed in a baggie and wrapped in some bubble wrap will fit in 1/2 a cigar box. Call Jim Patterson, one of the owners and the service manager at Dixie Diesel, to tell him what you want and to let them know you are sending the injectors to them, then ship them UPS or USPS. They usually have a very fast turn around time.

The injectors will come back looking like new complete with gaskets, o-rings or sealing washers as needed.

800-523-4621
931-381-1647
200 E 16th st.
Columbia TN 38401
 
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Lol...I’ve got a 3 cylinder genny.

Might be worth a shot. Ive read other owners improved it with injector service and some new isolation pads. I still think it will be easier to accomplish out of the boat as opposed to hanging upside down.
 
Frank and Carter.

Back to the HEX. I'm thinking through the HEX removal and testing. I was thinking of removing it whole (not pulling the bundle and shell apart) and having both the fresh water and coolant side tested before making any decisions and or purchasing parts . Any of course I might as well clean them while I have them out of the boat. I have no idea when or if they have had anything done to them, si I would assume a good build up of scale and other marine life.

Is this the proper method? And who do you recommend for this service? I doubt I'll find too many places that have seen a CAT marine HEX in ATL, but I can ship out easily or drive them as necessary.
 
Any radiator shop can clean a marina heat exchanger.

Cat sells an O-ring kit for the heat exchangers. So take the o-rings to the radiator shop and tell them to replace all the o-rings and not to try to reuse any of the old ones.
 
Anybody know the material these HEX shells were made from? I scraped some paint off to do an closer inspection thinking they were some kind of steel from the way the paint blistered, but I don't think that's the case. I would have expected copper or marine grade alloy in any case.

Regardless, they appeared to be quite solid, so I'm questioning if they are even leaking. It may have been a small amount of ELC dripping down from the expansion tank lid when I pulled to inspect the coolant.
 
The O Rings are cheap and readily available at CAT. Maybe just pull the end cap and take a look at the facings...

When I pulled mine, found a lifetime supply of broken impeller blades - as frank says - CAT over designs their cooling systems, and I was glad of that. Mine never ran a degree above normal, but I don't see how water was flowing through that mess...

Oh - I recall the end cap is a composite material...
 
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End caps are composite. Now trying to determine if I even have a problem.

Over the course of the last year coolant levels were normal, started at the cool line, and rose to the hot line like clock work. That changed over the winter. Obviously running a lot less, but the level slowly dropped over the winter. At first, I attributed it to colder temps causing contraction. Was only like a 1/2" down.

Then I found a very small amount of coolant behind the starboard engine. Looking at the HEX, I saw severely blistered paint, and I assumed that it was corroded and leaking. Peeled the paint off, looks fairly solid.

Going to monitor this before I tear it apart. It ran fine over the last year. I put a pad underneath the HEX and if need be I'll wrap one around it to see if I can pinpoint whats going on.

Scratching my head a little over where the coolant came from.

Hmmm...
 
Can you pressure check it with a radiator pressure tester? I don’t own one. Up until 2 years ago my friend owned a local auto repair shop so I was always able to borrow his.
If you don’t have one, maybe you can borrow a kit someplace.
I’ve heard that places like Autozone loan tools. Maybe try them.
If there is a little drop in pressure, my money would be on the O rings for the end caps.
 
JVM225 said:
Can you pressure check it with a radiator pressure tester? I don’t own one. Up until 2 years ago my friend owned a local auto repair shop so I was always able to borrow his.
If you don’t have one, maybe you can borrow a kit someplace.
I’ve heard that places like Autozone loan tools. Maybe try them.
If there is a little drop in pressure, my money would be on the O rings for the end caps.
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That's a great idea!! I love CSR.
 
dtfeld said:
That's a great idea!! I love CSR.
Click to expand...

Just rethought this and realized that a drop in pressure on the antifreeze side probably isn’t caused by the end cap O rings. I think they only provide a seal for the raw water side.
But still a good idea to pressure test the antifreeze side to see if it holds pressure and if it doesn’t you will probably be able to see where it is leaking from
 
Can’t remember if it’s indicated on the cap of the HEX, but I usually just pump up to whatever the PSI on the caps indicate and no more.
 
Looked at the pad, no drippage, at least at rest, so I'll see if I can borrow a pressure tester and keep it below 13 psi.

Maybe chasing ghost. That would be a fine outcome.
 
dtfeld said:
Looked at the pad, no drippage, at least at rest, so I'll see if I can borrow a pressure tester and keep it below 13 psi.

Maybe chasing ghost. That would be a fine outcome.
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A wise man once told me that some of the best successes are the simplest!!!!!!

Bennett
 
Who was that Bennett? Seems like I've heard it before!

Cat engine have a bunch of hose clamps on them. When you move a boat from South Florida to someplace that gets freezing temperatures, hoses contract with the first cold snap. Before you tear apart your cooling system looking for a leak, try tightening all the hose clamps near and above the heat exchanger.

I bought my boat when she was 6 mopnths old/35 hours on the engines. THe boat was ordered, built and delivered in May. The next January, Panama City had a 3 day cold snap with temps not getting over 32˚. My next trip down I found a bilge with puddles of red Cat ELC everywhere. I spent a morning wiping every hose clamp with a paper towel; found several wet and retightened every hose clamp I could get to. That was in 1997 and I haven't had a coolant leak since.
 
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