idle adjust

[DThibault]

93, W350 manual transmission, The thing rattles and buzzes and it sounds like the idle is lower than my 91 of the same model. I wish I could put a meter on it but no such animal. I tried to turn the idle up yesterday and was unsuccessful. There is an obvious 10mm bolt that looks like if you loosen it you can move the lower tab out against the stop. No luck If the stop is a screw that you turn it is in a heck of a place to get at. Is there anything else that would make this thing not run smooth? It has plenty of power and seems to get smoother as I rev it up but not like to old 91. What to look for. Thanks.

 

[JLEONARD]

Yes the idle screw is a female dog to get at. My idle is low at about 600 but it is smooth.

I have an optical tach in Torrington, Ct... if it's worth the drive for you we can check and set the idle.

Jay

 

[dpuckett]

You can use a flat screwdriver and hammer to break the jambnut loose, then turn the screw to where you need it.



Injectors being out of balance in terms of pop and flow can make a rough idle, too.



Daniel

 

[DThibault]

dpuckett, the injector thing is what it seems like. The PO put a new injection pump on it so that should be OK> How does one "balance" the injectors? Do you just take them out and have the pop off pressure checked? Do you ever just replace the weak ones or do you put a whole set in? Thanks for the info.

 

[DThibault]

dpuckett, the injector thing is what it seems like. The PO put a new injection pump on it so that should be OK. How does one "balance" the injectors? Do you just take them out and have the pop off pressure checked? Do you ever just replace the weak ones or do you put a whole set in? Thanks for the info.

 

[sdstriper]

The nozzle pop pressures have a minimum and maximum pressure range, by matching them you should have a better running engine at idle for sure. From what I read you will not be able to notice much performance wise and may notice a very slight difference in economy. The Mercedes and VW crowds have a number of members who test and adjust their nozzles, that's where I first saw a homemade nozzle tester. For the Mercedes crowd the injecter shim washers are harder to get unlike for our trucks.