LDS VS LDT and the real differences

[rustystud]

Your post is a little confusing. The LD/LDT/LDS465-1 had two-hole while the LDS465-1A and LDS465-2 both had one-hole injectors (per TM9-2910-226-34 dated 1974). Seems a little odd that this TM doesn't require that the one-hole injectors should be replaced with the two-hole. Is the LDS troubleshooting manual the only place where this is said?

However, White and Hercules used the two-hole injectors on equal or higher horsepower equipment so it would seem that there is nothing wrong with the two hole injector as far as horsepower or engine longevity.

Agreed. Everything I have read on the two hole injectors was that they where to replace all one hole injectors as they performed better in fuel economy and power.

 

[ShawnIfert]

I reduced the fuel 6 flats and took a 20 mile drive today. The truck is running great. I had an Egt of 1025, so I am going up to flats on the injection pump. The new rocker arm were tight and the engine had some valve train noise for about 17 miles, but that quited down. There is a lot more power and the clutch slipped some. I will have to adjusted the clutch and adjust the injection pump and go for another run. The engine sounds completely different and the power curve has changed big time. It has a lot more low end grunt.

 

[rustystud]

I reduced the fuel 6 flats and took a 20 mile drive today. The truck is running great. I had an Egt of 1025, so I am going up to flats on the injection pump. The new rocker arm were tight and the engine had some valve train noise for about 17 miles, but that quited down. There is a lot more power and the clutch slipped some. I will have to adjusted the clutch and adjust the injection pump and go for another run. The engine sounds completely different and the power curve has changed big time. It has a lot more low end grunt.

Shawn, did you just add the new rocker arms for this increase in power ?

 

[ShawnIfert]

My egt's were 1100 with the stock injection pump, rocker arm and injectors. Egt's of 1100 was my base line for the test. I then installed the lds rocker arms my Egt's decreased to 900. The engine had a different sound and more power. My fuel pressure was around 425 and I did want to blow the injectors apart by upping the fuel pressure. But the test proved that there was a lot more air entering the engine. I then installed the reman lds 1a injection pump and nos lds 1a single hole injectors, my egt's went to 1300. I then turned down the injection pump 6 flats and my egt's were at 1025. I am now going to up the injection pump 2 flats. I went 6 flats down because I believe going up in pressure to your goal is more accurate and is not prone to change the same as a hydraulic system, which the injection pump is.

 

[ShawnIfert]

I turned up the fuel two flats and it seems to be the sweet spot. I have turned down the injection pump 4 flat from it original setting. Ambient temperature durning the test was 35 f. I went around on the back roads up down hill for 10 miles and everything was good Egt's of 1100 f turbo boost 13 45 mph 2000 rpm. I then took the truck on the interstate for 20 miles at 55 mph up and down hill. Highest Egt was 1125 f turbo boost 16 psi 2200 rpm on the interstate. When the Lds a1 injection pump goes full fuel you can really feel it. The turbo boost goes up to 16 psi in a flash and you just hear the engine sucking air!!! The engine stayed cool the whole time it never went over 180f. I do not have a hot water cab heater. I have a (multi fuel) cab heater. All the numbers look good for now. I may need to adjust it in the summer.

 

[The King Machine]

I turned up the fuel two flats and it seems to be the sweet spot. I have turned down the injection pump 4 flat from it original setting. Ambient temperature durning the test was 35 f. I went around on the back roads up down hill for 10 miles and everything was good Egt's of 1100 f turbo boost 13 45 mph 2000 rpm. I then took the truck on the interstate for 20 miles at 55 mph up and down hill. Highest Egt was 1125 f turbo boost 16 psi 2200 rpm on the interstate. When the Lds a1 injection pump goes full fuel you can really feel it. The turbo boost goes up to 16 psi in a flash and you just hear the engine sucking air!!! The engine stayed cool the whole time it never went over 180f. I do not have a hot water cab heater. I have a (multi fuel) cab heater. All the numbers look good for now. I may need to adjust it in the summer.

Nice work on your truck Shawn, I just finished a pile of work to my engine and I am pulling very similar numbers. I have yet to see 16psi on the boost, I believe I've reached a mere 14psi. My EGT numbers are almost exactly what your getting under similar conditions.

I will note that I could easily surpass 1300 if I was not watching. My truck came with the 2 hole injectors. The power is night and day, making a left turn on some wet roads the other day I swear I could feel the rears tire spinning as I was trying to make the turn.

 

[ShawnIfert]

My turbo is new.

 

[ShawnIfert]

The egt's is why I turned my fuel down four flats. I had the same reading on my first run of 1300 f.

 

[ShawnIfert]

I am sorry for this after thought, but I put the five tone piston liner kits in my truck and the kit came with duel nozzle piston coolers where the originals were single. Just a FYI!

 

[ShawnIfert]

I have worked for years in a test manager of a test department for a major drilling rig manufacturer certifying engines, cooling packs and other systems that are installed on the rigs with the involvement of cat, Detroit and cummins to pass there warranty criteria. The engines I have worked with are up 12 cylinder 32 liters. The numbers are good.

 

[rustystud]

I have worked for years in a test manager of a test department for a major drilling rig manufacturer certifying engines, cooling packs and other systems that are installed on the rigs with the involvement of cat, Detroit and cummins to pass there warranty criteria. The engines I have worked with are up 12 cylinder 32 liters. The numbers are good.

I always like working on those large engines. The biggest I ever played with was a 16 cylinder Detroit. Basically 2ea. 8V92's bolted together.

 

[rustystud]

I am sorry for this after thought, but I put the five tone piston liner kits in my truck and the kit came with duel nozzle piston coolers where the originals were single. Just a FYI!

Do you happen to remember what the pistons looked like ? How many rings and such ?

 

[ShawnIfert]

Part number 57k1318.

 

[gringeltaube]

Ahh... I think I know what the next question will be, then.

 

[ShawnIfert]

Here is a pic I took today of the other side of the intake and engine bay. Getting rid of the m35a2 filter opens things up a bit.

 

[rustystud]

Ahh... I think I know what the next question will be, then.

I wonder if "wildchild" has seen these pistons ?

 

[gringeltaube]

No, not that question...


Still, if you refer to post #652 the answer would be no, Wildchild467 did not see it yet. (According to the list of readers he has last opened this thread on 12-09-2015 at 17:03)

But he sure did see this post, and I firmly believe that that is exactly the same kit he as well as ShawnIfert; cattlerepairman; Clay James - plus everyone else on this board doing a similar job - has used so far.
The mystery remains...



G.

 

[ShawnIfert]

I did not measure the ldt piston that I had removed. I looked at both ldt and the lds piston and I did see a difference. The only thing that was different was the duel tip piston cooler that came with the lds kit. The other difference was the oil port on the lds rocker arm that pools more oil on the top of the combustion chamber.
With the lds piston installed the truck is harder to start in the cold unlike the ldt pistons. I installed the Pistons and liners with my ldt injectors, ldt rocker arm and ldt injection pump and ran the engine for 100 mile before I did the rest of the mods to my engine.

i have had brand new engine melt a piston from a piston cooler coming apart and that piston melted in like 30 mins under the full load test that I was running on MTU 2000 V12. My point here, is maybe the only difference is better piston cooling

 

[rustystud]

Could be right about the cooling Shawn. Since the LDS is making more power there would also be more heat to deal with.

 

[74M35A2]

Wildchild467 has as high as a 95% leak down rate on his freshly rebuilt LDT/S hybrid engine with those pistons/rings, we just measured it last night with a new head gasket torqued into place and the rocker shafts left off. Piston tops look good, suspecting broken rings or ring lands. No valve leakage, NOS heads. We're not exactly sure what went astray, I'm blaming too much boost and/or unknown WMO fuel source for now. Could be anything in there, people at the dump don't care. His as-removed rings were also shattered, so that is two sets now. Suggesting he re-ring his previous pistons, back boost down to spec level, and empty/flush his fuel system completely and break it on in fresh, clean, diesel fuel only. If anybody else has done an LDT/S conversion (attempt), please get ahold of him and tell him your setup (boost level, fuel type, LDS conversion pieces added to LDT, and any data you may have such as compression or leak down). His truck ran strong at first, pulling away from my 925A2 off a light up to 55mph, then quickly lost power and turned into a steam engine via blow by out the draft tube and oil turning to sludge under the valve cover. He has a separate thread going near the top of this section, sorry I didn't copy the link to it before drafting this, but most of you will know him and his current situation. Thanks for the 66 pages of fun.