3126 Cat engine down , fuel running into rad . Well I got a 2002 Sterling Dump truck . last Saturday the engine started pump fuel into the rad and overflow . I figure the seals on the injector tubes got hot and all went downhill from there. It is a 250 hp engine . what other Cat 3126 can I put in there without messing with turbo , injectors . or the ECM. People have told me that I have to stay with the 250 hp class or larger which I want to do . Is there any changes if I find a 300hp ? Thanks
First of all fuel in the rad is a common failure even without overheating. It is easy and cheap to fix. Second question is why don't you rerate the 3126 you have. That should be cheaper than swapping the engine. I would have to check the rerate chart but I think 250 can be rerated higher without injector changes.
Whats your serial number?
Thanks for the reply Mobile, although the engine only had 70,000 miles on it , it had other issues . It was putting compression in the rad from a crack in the block at the pass side front of block right at the mating surface of the head . I welded it and stopped the leak on the outside but I guess it was cracked into the water gallery . I suspect that's what cooked the injector tube seals . So It was not worth fooling with as to installing new seals , it would probably happen again . So I have the engine out now . Quite a job to remove from a short nose Sterling . Thanks for the reply .
There have been other examples on here of users trying to swap, re-rate, or otherwise screw around with 3126 engines. In a nutshell it is not as easy as many "Tuning experts" would have you believe, the word they put out is flashing software that gives more HP into the ECM is all that's required. A lot of re-rates involve iron changes such as (but not limited to) rods/pistons, turbos, & injectors. A poster on here got burned by one of the aforementioned experts, he paid a substantial amount of money and got no more HP because the iron wasn't changed. You really need to look for a 3126 that is the same Arrangement Number as what's on the S/No plate of your failed engine.
Yes you need to do the iron changes too. No short cuts. Cat usually just changes turbos and injectors. There is a rerate chart from cat that lists changes required. You won't get a lot of improvement on a 3126 with a rerate. They don't have the torque like a C15 can produce when uprated.
I believe its an 8YL 55085
What is the torque rating of your transmission? It may be to weak for an upgrade. I had the same issue with my 2001 Ford F 750. Cat would not do the upgrade due to the tranny being to light.
according to Cat that was a 210 hp 520 lb ft engine from factory. Was it already rerated to 250. If it started at 210 it will need at least injectors to get to 300. I guess you were going to another engine anyway . Were you going to use this ECM.
Sorry I'm late getting back to you guys . As for the tranny rating . I have no idea , maybe there is a number or a spec plate on the side of the tranny that I can get some info . As for the engine rating, there is a decal on the valve cover saying its 250 hp , so I was hoping I could get another engine in that hp range. Not having much luck here in Newfoundland so I'm going to try to find something on the mainland (Newfoundland is an island ) or something out of the US. I was hoping that I could at least go to 300 hp without having to change anything especially the electronics or any internal iron . What do you guys think ? , If I have to stay with a 250 hp engine I will be happy but not having any luck here. There are some engines on ebay and other places and some are 330 hp out of RVs with very little millage on them , hence that's where the idea of going with the 330 hp came from . I certainly appreciate the info help guys . BTW anyone have an engine ????lol
The failure rate is pretty bad on these engines. I wonder if the failure rate is even worse on a higher HP engine. RVs and fire trucks get special treatment because of the low usage but my experience has not been that great.
The 330hp variations were for fire truck's and Rv's. If your looking for more grunt, you need a larger engine. The 3126 is a very reliable engine when it is used in the correct applications. Unfortunately it had a way of finding it's way onto trucks it had no business being in. Shop I worked at serviced hundreds of trucks with these engines and other then the occasional injector issue and some high pressure oil lines and IAT valves most ran like tops well over 300k of city pick up and delivery duty with the owners doing the minimal of PM
You didn't see the usual HEUI pump failure fragging the hydraulic system and causing lingering issues for the rest of the engine's life, or bottom ends grenading? Just wondering what the regional differences may be....
Only a handful of HEUI pump failures, and no bottom end failures whatsoever. If we got a 3126 to work on it would usually be one of the following issues -Oil leak at oil cooler. Very common. -IAP valves or sensors, high pressure oil line. They kepts updating from a steel tube to a rubber hose to a tube, to a hose... -Engine speed sensor issues. -Injectors or injector seals -Oil leak from front crank seal, and occasionally front cover but usually only on higher miles units. -Overheating and would find the water pump belt missing. These things would constitute ~80% of all 3126 repairs. We would get other things but not with any kind of regularity. Just thinking on the bottom end failures, a bit over 10 years ago we had a GMC T6500 in the shop for a excessive smoking and lack of power complaint. Tech goes out does a few checks and decides to take it for a quick boot. A few mins later he pulls back into the yard and the thing is smoking like a total pig. Gobs of billowy black/gray smoking pouring out of the tailpipe. He got just into the yard went it took off and ran away. I'll never forget the noise of that engine just screaming. We thought for sure it was going to completely grenade. Well after what seemed like forever and what was probably 30 secs it starting to slow down and finally sputtered to a halt. Towed it in, and turned out to have a blown turbo seal. He replaced the turbo, changed what was left of the oil and fired it up. No knocking. Could not believe it. It had quite a bit of blowby but ran down the road for a number of years.
When do you typically see the turbo start to spool? At what RPM? What do you usually rev the engine to?