Lack of power

[Firewoodjoe]

Forwarder is way behind so I'm out here skidding this weekend. In machines with torque converters is the lack of plow end power and engine problem or a torque converter problem. Like if you add more power to the same trans/converter would it work better. Just skidding and thinking 🤔

[barbender]

Is the engine loading down? Ponsse forwarders don't have a torque converter, they have a drive pump to a driven pump on the transmission. I never had one lack for engine power, it was always the hydraulic relief settings that would give first. It is quite frustrating when you are climbing a hill, everything is going fine but then the machine just stops without the engine even bogging down. 

 One machine had to have the cutter pressure adjusted at least once a year, I wouldn't realize there was a problem until I got on a hill job and it wouldn't climb, or if I was on a job with another machine I would realize how much travel speed I lost when their machine would walk away from me. 

[Firewoodjoe]

It works as a torque converter should. It bogs yes but at its lock up rpm. And it will spin in first gear of you want it to. I know performance converters you can pick the stall speed. I'm wondering if I could improve this buy going to a 140hp engine vs the 115 it has. 

[Gary_C]

I had a 546 harvester and found out really quick it was not the most speedy machine when loaded, especially in snow. I always ran tracks and soon found out you could not shift the torque converter into 3rd unless you were already moving. Even then the Ford 4 cylinder BCD engine in those 500 series valmets lacked power in all applications and could not be upgraded. My understanding was the 546H was modified perhaps with a longer stroke crank to up the power slightly but was still not up to many tasks, especially driving with a load. And as far as I know, there was no replacement for that Ford BCD engine. That was one of the reasons for Valmet moving to the 600 series machines with the Cummins Engines when Ford discontinued that BCD 4 cylinder engine.

[Firewoodjoe]

Mine is a 646 with the Cummins. There's a lot of crate engines with different hp available. 

[Gary_C]

My mistake, I thought you had a 546. I had an early 644 forwarder with a manual transmission and it was a dog also. 

The early 646 forwarders had a terrible vibration problem because Cummins did not put engine balancers on any of their engines at the time and those early machines shook themselves to pieces and Valmet had to recall all of them and put on the engine balancers. They would shake the air cleaners off the engine mounts and then destroy the rings when they had no intake air filtration. Even then with that recall, everyone complained about lack of enough power and eventually the next series came with a six cylinder engine. I think it might be possible to put a six cylinder engine in place of a four with different motor and radiator mounts but it would be an expensive upgrade.