Notice: We request that you don't just set up a new account at this time if you are a previous user.
If you used to be one of our moderators, please feel free to reach out to Chris via the facebook Outerlimits4x4 group and he will get you set back up with access should he need you.
Recovery:If you cannot access your old email address and don't remember your password, please click here to log a change of email address so you can do a password reset.

Timing issue?

Tech Talk for Mitsubishi owners.

Moderator: -Scott-

Post Reply
Posts: 146
Joined: Thu May 07, 2009 3:10 pm
Location: Sunshine coast QLD

Timing issue?

Post by Jonezy01 »

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
Posts: 14209
Joined: Sun Jan 11, 2004 11:36 am
Location: Adelaide

Post by -Scott- »

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?
Posts: 146
Joined: Thu May 07, 2009 3:10 pm
Location: Sunshine coast QLD

Post by Jonezy01 »

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
Posts: 146
Joined: Thu May 07, 2009 3:10 pm
Location: Sunshine coast QLD

Post by Jonezy01 »

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

Jonezy
Posts: 511
Joined: Tue Jan 15, 2008 1:33 pm
Location: Cooma NSW

Post by date »

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.
Posts: 212
Joined: Sun Apr 19, 2009 8:40 am
Location: Branxton

Post by phat-customs »

Harmonic balance could also be slipping. I assume there a Steel/rubber/steel config???
The Box-Kite Paj: Gone...
Now: 96 TDI Disco, 2" Lift, 265's and a leaky windscreen...
Post Reply

Who is online

Users browsing this forum: No registered users and 2 guests