Outer Limits 4x4 Board

Hey fellas lately my 2.6 (4G54) is loosing it's timing. I ran timimng light over her about a month ago but now shes running even more advanced than she was before, can anyone shed some some light on what wrong/what needs replacing and wether its a easy enough job to do?

Cheers Jonezy

Hi Jonezy

NFI why it's advancing. Are you sure you're measuring without the vacuum line connected?

If it's retarding, that could be a result of the rubbing block wearing down over time (presuming it's traditional points - is it?)

When you do the timing do you also check dwell?

Cheers for the reply scott.

Im relatively new to petrols so dont know to much about them.
Im only asuming that the timing is advanced because the fuel economy has shot through the roof (over double normal) and back fires like a mother fawker under engine breaking and the strong smell of fuell when at an idle.
I did the timing a little over a month ago and these symtoms disapeared (fuel comsumption returned to normal ect...) as for the vacume line i have know idea what this is so i guess that this was still attached when i did the timing.
Once again have no idea what the dwell is?
Im 90% sure that it still uses points, but could be wrong.
My old man said he would give me a hand to do it as he knows a little(Not a lot). But any knowlodge you can give us would be a big help.

Cheers Jonezy

Corection, just had a look this morning and it doesnt use points.

Jonezy

Jonezy:

A simple way to check what is happening is to observe the ignition timing position. You need a timing light to do the following. Disconnect the vacuum and rev the engine to say 3000 R/min. See if the timimg position changes. How much? You should have probably 15 to 20 Degrees change (more advance) compared to the static position (about 10 Degrees advanced). Then, get the vacuum hose and suck on it whilst watching the ignition position. You should get a similar change of timing mark.

Inside the distributor, there are centrifugal weights which swing out further as the speed increases. They are restrained by small tension springs. Maybe one of the springs is weak/broken/stretched, thereby allowing centrifugal advance to come in earlier? If you want to see the weights and springs, you have to dismantle the distributor.

Set the engine to Top Dead Centre on No 1 cylinder (this is for reference when you replace the distributor). Note the position of the rotor button. It should probably point to somewhere where there is a notch or mark in the distributor cap. This is your reference. Remove the distributor from the engine. There should be two shafts - the lower and the upper section (where the rotor button fits on). Sometimes these shafts stick together. When you replace the distributor, make sure that is goes all the way down to fully engage the gears. Remember that the gears are spiral and you have to allow for this when inserting the dizzi back into the hole.

Check that the rotor button can rotate slightly. The distributor has centrifugal advance (refer above re weights) and vaccuum advance. The Centrifugal advance is done via the shaft where the rotor presses on. That is actually separate from the lower part of the shaft where it engages with the camshaft. You should be able to get a small amount of rotation - about 10 Degrees only. This is the centrifugal advance.

The vaccuum advance comes from moving the distributor baseplate. This is activated by engine vacuum operating on the diaphram, dragging the baseplate relative to the distributor body. The magnetic pickup whcih tells the coil when to fire is attached to the baseplate and moves slightly (again abot 10 to 15 Degrees) depending on what vacuum is being generated by the engine.

Is can be cpmplicated, but if you do the initial checks with the engine running and you get centrifugal and vacuum advance of the order noted above, you can probably rule out the distributor as the cause of your problems.

Harmonic balance could also be slipping. I assume there a Steel/rubber/steel config???