Wastegate operation 617 952
 

ok, as most of you know by now I have a bastard 617 952. From reading in here I think I understand that 617 turbo's wastegate could be opperated via vacume or pressure. Plumbed different ways obviously but either will opperate the wastegate.

I'm trying to determine what in the hell I have. What prompted this question is someone said there was a rubber hose from the intake to the wastegate. wellllllll... unless Im looking in the wrong place I dont have that. I well could be looking int he wrong place when looking at the turbo cause I dont know where in the turbo arrangement the wastegate is. Looking on the intake side I did not see a hose comming from it.

Can anyone map out the typical locations of the two varients (pressure or vacume) plumbing so I can determine what I have. or point me to a web site with some pics or break down drawings.

Thanks in advance

There should be a steel can on the side of the turbo and a short piece of hose attaching from it to the pressure section of the compressor housing. The can houses a preloaded spring that holds the wastegate shut. When boost reaches the setpoint the boost pressure overcomes the spring pressure and opens the wastegate to relieve some of the boost. The steel can has a cover held on with a spring clip. Pop the spring clip off, remove the cover and you can adjust the boost pressure by increasing the spring preload. I have heard that putting the cover back on is a be-atch. You may have a different type of turbo but I think all 617's had the same one? RT

Thank you sounding a little familure. ahhhh...... compressor housing is??????? I assume portion of a compressor... ahhhh.. where is this compressor? (looking at my feet embarased to be asking such simple questions)

If I am to adjust the wastegate it will be with installing a pressure regulator in the hose . NO WAY is it possible to get to the can (if I think it is, where I think it is) in this Unimog.

Hey Coach,
"Compressor" = turbo, same thing - different name. I've got an 84300D and even there adjusting the preload on the wastegate spring is a pain. There are lots of aftermarket boost controllers that you could plumb in. I just cut the rubber hose from intake to the wastegate and installed a simple brass needle valve. Then I loaded the engine per the manual (about 2500 rpm, full load, in 2nd gear, I think) so that max boost was about 12.5psi. Spec upper limit is around 14psi, maybe 15 psi. Made sure that 12.5 was the highest point even as boost spiked with shifts under load. Then I turned the ALDA screw a total of 1/4" turn so the injection pump would provide extra fuel to go with the extra boost. Much better performance all around. The Unimog looked really cool in those pictures...now that's what I call an ATV!

Fre

Thanks Fred, very practical information.

Can this pressure for the wastegate be brought in from some place else like the back of the intake manifold at the other port that is below the banjo bolt? Or is this not another port? This would be reaaaaal advantagous to me if so.

Also, where the pressure comes from now for the wastegate (the spot on the housing for the turbo)... what is in the housing at that area, just passage way of air or is the impellor right there orrr?

I'm thinking where the wastegate hose is now would be a good spot for LP or water/alcohol injection and where the spot in back would be a better place for me for wastegate pressure cause I could then easly put in cab boost controll cause of its proximity to the upper dash on the Unimog.

TTT... making plans.. well trying too. ... This info would greatly help

feeling impatiant. sorry.... Hope ya dont mind.

so what tya think? Can I opperate the wastegate from a different source or pressure besides where it comes from right now?

Please review my previous post in here for more details and other questions.

THANX again.

There's no turbo used on an OM617 that had a vacuum-operated wastegate. Onlt the 1990 and newer OM602 turbos (and possibly OM603) had that, with the computer controlling the vacuum signal & boost. The 617's are pressure operated only, purely mechanical.

Thanks Gsxr for clarifying that. Deeper into this thread the questions evolved beyond that. Since they did I guess Ill repost.