Official Caterpillar3116/3126 Thread

I'm working off memory here but I think my GFs brother-in-law said no these engines are not sleeved.

theyre definitely not in the sense we normally talk about where the coolant contacts the sleeves and they can be removed with the pistons for an in-frame rebuild (in a truck). What the guy claims is there is a steel sleeve in the block, press fit in, because the iron can’t withstand the pressure. I think that’s incorrect

they do make sleeve kits for these engines but it requires boring the block out to fit them
 
Not being a sick, but I think you mean if the impeller has threads not the housing. I have never seen the impeller without the threads
You are correct, meant to say the impeller. Unfortunately, the PO of my boat bought impellers that weren't threaded, from Seaboard. The starboard side impeller was frozen onto the shaft. Not enough room to get a puller in there even with exhaust tube removed. Had to pay a mechanic to finally get the thing out. I had bought the replacements from CAT and he noticed they had the threads. He told me to always use the ones with threads. Hopefully the non threaded ones aren’t available anymore. Cost me a lot of money to get the stuck one removed!
 
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I had bought the replacements from CAT and he noticed they had the threads. He told me to always use the ones with threads. Hopefully the non threaded ones aren’t available anymore. Cost me a lot of money to get the stuck one removed!

If I'm reading this correctly you're stating the impellers should have threads and to buy them directly from Caterpillar?
 
I buy them from CAT and look at them to make sure because of the trouble I had. I’m on my 3rd set since that happened. 7E 0321 is the PN I use.
 
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Same ones for the 3116 (at least it is for mine). That puller looks interesting, would be handy to have. I just ordered this one, similar price but no puller: https://www.amazon.com/dp/B0115RA2C2?psc=1&ref=ppx_yo2ov_dt_b_product_details
This looks to be the same kit, with the puller:

https://www.amazon.com/StayCoolPumps-Impeller-Replaces-Sherwood-17000K/dp/B0859NYHK3

This is such a critical part of these engines, I'd had to go "cheap", save a few dollars, but it breaks/wears down sooner. Is one better than the other? Meaning, if I order from CAT or Amazon/eBay/Sherwood, am I getting the same quality from all? Tough question I know without doing a side by side comparisons, which can probably only be done if you replace them in both engines, at the same time, with one from each.
 
Here is a solution to "going cheap":

Buy Sherwood #17000K impeller kit for the 3116 engine (Sherwood pump # P1710C, Cat # 4P-7168) or the 3126 engine (Sherwood pump # P1732C, Cat #170-6116.

Sherwood is the OEM supplier for Caterpillar for both pumps and pump parts. The impellers usually delivered in a cardboard box without the keys, and o-ring, then Cat is happy to sell you keys, and o-rings separately. I usually pay $50 for the Sherwood kit and my neighbors at the marina are paying $94 for the impeller from the Caterpillar store.

Always buy the Sherwood impellers from a volume distributor so you avoid getting old impellers that have been sitting on a shelf in a hot warehouse for who knows how long and are dried out and brittle because they have a very short life remaining. Avoid discounters, surplus sources and eBay sellers.

Remember…... this is a cheap but critical part in the health and longevity of your engines and is not the place to try to save a little money.

On the T-handle threaded impeller puller, they probably work OK on some boats but Sea Ray used Teleflex gauge packages. Most oil pressure senders on 3116 and 3126 engines mount right in front of the sea water pump and will interfere with the rotating the T-handle on the impeller puller, so it may not work as intended.
 
Hi all !
For Cat sea water pump is recommended Steve from Stay Cool Pumps , call him very helpful.
 
Question do you use guys Rotella T1 30W oil for transmission ?
 
Yeah, depends on model. We have hsw800-v2 and I believe anything in that series requires dexIII ATF. We use Mobil synthetic
 
You are correct, meant to say the impeller. Unfortunately, the PO of my boat bought Sherwood impellers that weren't threaded, no idea where he got them. They we definitely Sherwood. It’s in his service log but no part number. The starboard side impeller was frozen onto the shaft. Not enough room to get a puller in there even with exhaust tube removed. Had to pay a mechanic to finally get the thing out. I had bought the replacements from CAT and he noticed they had the threads. He told me to always use the ones with threads. Hopefully the non threaded ones aren’t available anymore. Cost me a lot of money to get the stuck one removed!

Sorry for posting incorrect information. The impellers w/o the threads were from Seaboard, they were not Sherwoods.
 
Here's a cut and paste from Dr. Webster:

"It is much handier to get a 3/4"-16tpi about 1-1/2" long then use a socket/rachet or even better a racheting box end to screw the bolt in the impeller hub and jack the impeller out of the pump housing far enough to grab it."

RWS
That's the advice I followed from him last time I replaced my impellers and it worked out really well. Dr Webster for the win (again!). After having just replaced mine yesterday, there's no way I would have the space or leverage to make the handle work, so I'll be sticking with the threaded bolt process.
 
Purging the air out of a 3100 series Cat engine is a real job. If you know what you are doing it can burn up 45 minutes…..if you have never bled one, think 2 hours.
Sadly I think I may be facing this myself. I replaced the Racors and Fuel filters last weekend, along with the priming pumps. I started them up yesterday once I had the impellers done, and the port motor ran for about 2 minutes, then got rough and died. About 5-6 restart attempts wouldn't fire it back up. I couldn't get the primer pump to work on that engine, so not sure if it was installed correctly or not. I finally stopped trying to restart while I figure it out, so as not to make a problem worse. Any recommendations on next steps?
 
Sadly I think I may be facing this myself. I replaced the Racors and Fuel filters last weekend, along with the priming pumps. I started them up yesterday once I had the impellers done, and the port motor ran for about 2 minutes, then got rough and died. About 5-6 restart attempts wouldn't fire it back up. I couldn't get the primer pump to work on that engine, so not sure if it was installed correctly or not. I finally stopped trying to restart while I figure it out, so as not to make a problem worse. Any recommendations on next steps?

did you crack the plug right after the filter to see if fuel is coming out? I usually do that when I replace the filter if it’s loud in the marina and I’m not able to hear the fuel returning to the tank. That will quickly tell you if you’re pulling fuel through the filter

also, and I don’t mean to insult because I know this from experience, did you turn your main shutoffs back to the on position?
 
did you crack the plug right after the filter to see if fuel is coming out? I usually do that when I replace the filter if it’s loud in the marina and I’m not able to hear the fuel returning to the tank. That will quickly tell you if you’re pulling fuel through the filter

also, and I don’t mean to insult because I know this from experience, did you turn your main shutoffs back to the on position?

This is an easy thing to do for sure...I've done it, especially if you are worrying about other things. Or forget to turn the knob on the prime pump.

Easy fix though.
 
I've been reading so much here about these priming pump issues, may just have to advance my schedule and get those Tee fittings, ball valves and electric fuel pumps installed.

Typically, an electric fuel pump will push better than it will pull.

I'd mount them in-line, between the tank and the Raycor so they can push fuel through the entire system. The valves would eliminate any possible restriction they may cause.

This way I can install the Raycors and the CAT fuel filters DRY.

No muss, no fuss, no messy filling of the bowls. . . .

This is the one I installed on the 10 Meter:

Amazon.com: Carter In-Line Automotive Replacement Universal Electric Fuel Pump (P4259) : Automotive

Well that price more than doubled since I last bought that item.

Here's one that comes with a pre-filter for a whole lot less:

Amazon.com: E8012S Universal Electric Fuel Pump Low Pressure 5-9 PSI 12V w/Installation Kit : Automotive

BEST !

RWS
 
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Sadly I think I may be facing this myself. I replaced the Racors and Fuel filters last weekend, along with the priming pumps. I started them up yesterday once I had the impellers done, and the port motor ran for about 2 minutes, then got rough and died. About 5-6 restart attempts wouldn't fire it back up. I couldn't get the primer pump to work on that engine, so not sure if it was installed correctly or not. I finally stopped trying to restart while I figure it out, so as not to make a problem worse. Any recommendations on next steps?
I may have missed it in an earlier comment; did you replace the entire pump, or just the cylinder?
 
I've been reading so much here about these priming pump issues, may just have to advance my schedule and get those Tee fittings, ball valves and electric fuel pumps installed.

Typically, an electric fuel pump will push better than it will pull.

I'd mount them in-line, between the tank and the Raycor so they can push fuel through the entire system. The valves would eliminate any possible restriction they may cause.

This way I can install the Raycors and the CAT fuel filters DRY.

No muss, no fuss, no messy filling of the bowls. . . .

This is the one I installed on the 10 Meter:

Amazon.com: Carter In-Line Automotive Replacement Universal Electric Fuel Pump (P4259) : Automotive

Well that price more than doubled since I last bought that item.

Here's one that comes with a pre-filter for a whole lot less:

Amazon.com: E8012S Universal Electric Fuel Pump Low Pressure 5-9 PSI 12V w/Installation Kit : Automotive

BEST !

RWS

i can’t think of any reason his wouldn’t work, and I understand what you’re after, but I’d consider posting this to a place like boatdiesel to get their opinion. The fuel system is critical and CAT engineers the shit out of everything, you’d hate to introduce any unnecessary issues
 

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