QuestionI am having trouble getting my 4.1 6 cyl to take timing adjustment to the oem specs,I currently need to set it very advanced to make it so that it has any power.When I do set it correctly it just plain has no power,and although it will idle nice and all,when asked for load ,it dogs.I have checked with the local parts store on Oxygen sensor,maybe thats it. or the vacume switch,located in the air cleaner.I dont know if one of those are the culprit.I also noticed that the rodchester 2 bbl carb,had been messed with,mainly because the control rod for the secondary choke has been bent up,like someone was trying to do something,to help.
The reason I ask,is some days the truck gives what seems to be great gas mileage and others ,it seems to drink gas like a guzzler.
I have resolved issues like vacume leaks,and the trailer lights pigtail shorting out on the body,affecting ignition voltages,etc....
I guess it bothers me yet, why it just wont run well at the spec'd timing,the little engine has 120,000 on it,and it is still very tight and does not use hardly any oil.Other than that it runs really nice,with the timing advanced,actually quite a bit,... somewhere like 14 - possibly 20 degress out,I think spec is 8 degrees,at least theres a little tube ,or what I call a site tube to set the timing at,and that is the Manufacterer setting on the label on the engine compartment,with spark plug gap and the rest.
Yes,..... I follow procedure in timing it.
Any info will help on what to check next,and how to check it,or test it,before I go buy parts.
I like backyard'n,on my vehicle's ,and I am 49 now and had these cars and trucks before.
This little delema is got me at a loss.
Im still wonder'n if I still dont have a vacume leak problem,so far I've checked and used a lot of starting fluid to find leaks.but now I cant detect any more.
Help
ps
one of my old trucks had a vacume leak down by the transmission,after doing a ton of stuff ,I discovered it.
But then the 350 engine ran like crap,no matter what I did.Til I discovered the stupid vacume leak down at the tranny,this situation could be the same but??????
I'll check there yet,while I wait for your advice.Still it runs nice ,just at a very advanced timing.
AnswerHey,
The little tube is not what you line TDC up with its the V right beside it. The tube is for the factory timing sensor that picks up the hole. If you are setting it with a gun you should clean off the tab and look for the 0 mark on the largest of 4 V's.
You have what is called a feedback carburetor. It is very important that the oxygen sensor is working properly to maintain fuel economy. The metering solenoids at the front of the carburettor could be causing a problem if the system is not going into closed loop.
Wayne
