[Steve-O]

Im Trying to set the timing on my GQ Patrol Rb30, There is a small issue though.

The emissions lable states 15 degrees BTDC , and doesnt say anything about Plugging the vacume advance hose. But the owners manual says 1 - 5 degrees BTDC and says to plug vacume advance hose. Now I also called nissan service centre and the guy said to follow the emissions lable and when i asked about plugging the vacume advance hose he said that if its not on the lable then dont do it.

Is the lable right and should i time it with the vacume plugged or not.

any thoughts would help.

 

[ST391GQ]

5Deg setting at idle (about 650 rpm) with vacuum hose to dizzy blocked.
When it is hooked up again should run at about 10-12 deg.

HTH.



Also make sure that the weights inside dizzy are working freely ....and that vacuum canister on side of dizzy is working OK. these are prone to split diaphragms on these donks...and id so ...yu will go nuts tryin to tune it hey. (dont even ask how I know this !!!!)

Cheers Keith

 

[Steve-O]

yeh my new advace diaphram arrives tomorrow, but I dont think when you put the hose on it should advance the timing that much at idle. a couple degrees sounds reasonable but 10 is a bit much, but im no mechanic so i might be wrong. I will put the new diaphram in tomorrow and ill let you know if it advances that much at idle. when the old diaphram was on it did advance that much but it was totally stuffed so i assumed that was one of the effects.

on the label it also states 800 to 900 rpm idle. I dont think this would be to much of a concern but I wouldnt mind getting as many k's out of the tank as possible.

 

[ST391GQ]

Hmmm....800-900 rpm ???

Gunna check my RB30 workshop manual termorra n git back to ya.

Cheers Keith

 

[Steve-O]

Ok new advance diaphram in and just set timing to 15 degrees with vacume advance hose still connected. When I took the vacume hose off the timing dropped to 4 degress BTDC. So vacume advance does advance timing by 10 degrees at idle. See this is confusing me, I though it is only supposed to advance the timing at around 3000 rpm. I took it for a spin to see if the little power band has come back at around 3500 rpm but no luck, so im lost.

any ideas guys.

 

[ITS A FORD NOT A NISSAN]

on petty motors i have always advanced the timing until it starts to ping (piston slap under load ) , then i just back the timing off till the ping stops , different grades of fuel will also determine how much advance you can run ie: the higher the grade of fuel , the more advance you can run

doing it this way you should get the most power and best economy out of it

 

[Steve-O]

on petty motors i have always advanced the timing until it starts to ping (piston slap under load ) , then i just back the timing off till the ping stops , different grades of fuel will also determine how much advance you can run ie: the higher the grade of fuel , the more advance you can run

doing it this way you should get the most power and best economy out of it

yeh I might just do that, cheers mate.

 

[GQWGN]

I have what seems like a ridiculous question....
Where are the timing marks to set the timing?
Last car I had that needed a timing light was a 327 chev and the timing indicator is right next to the crank pulley....

 

[Trav]

ok, ill try describe this as best as i can.
if you stand infront of your left hand headlight. lean into the engine bay over the left corner of the radiator. point your timing light from that angle towards the crank shaft. you will see i think its 6 marks on the belt. then there is a block sort of thing on the side of the crank shaft pulley with a line in the middle.
now according to the sticker on the rocker cover of my troll. the timing should be 15 degrees btdc. this is the 4th line in the direction of rotation (it should be rotating towards you from the describe position). the first line should aslo be orange or in the case of mine faded and imposable to tell so just count the markers.

 

[GQWGN]

Thanks heaps Trav.

I have a flat spot on acceleration and was going to do the timing.
The vacuum advance is stuffed so will replace that and have another shot at the timing

 

[Steve-O]

Thanks heaps Trav.

I have a flat spot on acceleration and was going to do the timing.
The vacuum advance is stuffed so will replace that and have another shot at the timing

The best and cheapest place to bye a Vacume advance diaphragm is from,

Advance Diaphragm Options
Po Box 1003 caboolture QLD, 4510
07 5428 0808

They sell them on an exchange basis. $70 + $30 deposit for the the initial purchase, this includes freight and a return bag. Then when they reciece your old one they credit your account $30.

Everywhere else charges $150 + and they not brand new only either. Nissan said they could get me one but would take a week and is new but was $160.

 

[Trav]

is your flat spot on petrol or gas (assuming its dual fuel). what sort of rev range is it happening in.