a few question on om617.950
 

Did a convertion to a Toyota 4 runner.

I have it in and running but it seems to be a dog? Ik lack of power. And I can't hit 50 MPH easily.
I have replaced the 2 fuel filters.
I also have some valve adjusting tools on order.
I did check the valves and they are all tight. Is this most likely the casue?
Sorry for the dumb to you questions but I am very new to diesel.

As soon as I read my Mercedes shop manual and understand it better I will check the IP and timming.

Try adjusting the ALDA, should have some low-end power gains there. Its that square thing on top of the injection pump with a vacuum/boost line going to it. There should be a slotted screw on the top, held in place by a locknut, loosen the locknut and adjust the screw out a little, or as much as you want. I think it only goes about 4 or 8 turns total, supposedly you are supposed to back it out a little at a time but I just backed mine out all the way and it seems fine, got a lot (relative of course lol) of low end power

From my understanding the al a has nothing to do with power except off the line or Max boost cut out?

Answer
 

Tight valves = compression loss.

Here is the engine manual free from MB.
Untitled Document

Here is a link that will help you
http://www.peachparts.com/shopforum/diy-links-parts-category/146034-fast-navigation-do-yourself-links.html



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X2 on adjusting the valves.

Before fiddling with the alda, make sure the Boost line going to the alda is clean and not plugged up.

At the rear of the intake manifold is where the boost line originates. remove the Banjo Bolt and clean any gunk out of it, then make sure the boost line is clean and open towards the Switch Over Valve, and then to the ALDA.

Spray in some Brake cleaner, and blow it out with air. If this line becomes plugged, the engine will seem doggy.

Charlie

The line is clean.

I am a bit confused ?

I have the switch over valve to 12v power when the ignition is on. And the ground to the over boost valve. If this is wired correctly the ALDA only will work with a boost of over 15PSI ?

So I am guessing I have the wiring incorrect ?

ok I think I got it now.
If I have things correct.
The pressure port on the intake sends pressure to the ALDA, witch intern sends more fuel to the injectors.
If the turbo makes too much boost or the waste gate fails the over boost valve grounds and shuts the pressure to the ALDA and reduces the fuel to the pump ?

If this is correct I was thinking the switch over valve was always closed and power opened it. but in truth it closes when power is added.

I unpluged the switch over valve and it was a night and day difference in power.
I check with it plugged in at the ALDA and no pressure, I unplugged it and now there is pressure and power.
If I shut the engine off and test the over boost switch and found there is ground it means the over boost switch is shot correct?

please define for us what you think the overboost switch is, and how you have it wired.

the overboost valve shuts off the flow of boost air to the alda, and should cut out the fueling.
the overboost switch is on the intake just in front of the banjo line, and it sends signal to the overboost valve to kill fuel.

It is a pressure switch, when pressure reaches a pre set limitl it completes the circuit at the switch over valve and stops the presseure to the ALDA valve to slow the fuel to the pump?

not sure what your plans are in terms of increasing power at some piont or just leaving it stock. But if it were mine the alda and over boost valve would be gone in a hurry. I would then check to see what boost pressure you are really getting , and at least set it to factory max of about 12 psi. Check fuel pressure coming into the ip also, this tends to get less over time as the fuel return valve spring gets weak and needs a little stretch to get fuel pressure back into spec.

Valves tend to get tighter over time from wear on the valve seat, so adjust them and keep a schedule of when you do it and then keep it up per the manuel. About 15,000 miles or so. You can do it without specail wrenchs but you may want to go ahead and get the correct ones to make it easyer.

I would like to keep it close to stock,
As for boost before I took off the electric plug at the switch over valve I was at 5-7 PS I, after I unhooked the switch over valve I am at 10-11 PS I boost.
And my valve wrenches will be here tomorrow.

Can you test the over boost sensore on the intake?

What gearing does the vehicle carry in its diff? is it an automatic? how much does it weigh?

The 617 is a fine engine with good power for its size boost etc. but it is nothing like a small block chevy for torque and power. It may be carrying gears that are too tall to utilize the power band of the diesel as it is now.

its weight is les than the 1980 300sd.
gears are 4.10s
5 speed