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Clive
01-16-2007, 09:01 AM
2.25 gas with 8:1 head (Turner motor) and Petronix ignition. I have been told that the timing chould be set at everything from 6 deg BTDC to 3 deg ATDC!! Can anyone tell me what it REALLY should be! At sea level, Florida, and confused.

singingcamel
01-16-2007, 09:52 AM
:D shooooooooot,
the best timing light i've ever had was a fruit jar half full of water.
directions for use easy to follow as well.
#1 loosen the dizzy at the base.
#2 set jar on the wing.
#3 advance or retard the timing until water in the fruit jar is as smooth as you can get.
#4 tighten the dizzy .
#5 to easy
www.singingcamel.com (http://www.singingcamel.com)

Jeff Aronson
01-16-2007, 05:07 PM
2.25 gas with 8:1 head (Turner motor) and Petronix ignition. I have been told that the timing chould be set at everything from 6 deg BTDC to 3 deg ATDC!! Can anyone tell me what it REALLY should be! At sea level, Florida, and confused.

Hi Clive,

The reason for the variation is that Rover did not know what the fuel quality would - or would not - be. The Turner motor with the 8:1 head will have great power [for a 2.25] but it might require mid-grade gasoline so as not to "ping" under load.

First, try some regular gas and set the timing to 0 degrees TDC. If you have any inclines, put the car in a high gear and force it up a hill. If you hear a "pink" or rattle under load, then it's running too advanced. Lower it to 3 degrees BTDC and try it again.

With a new engine, the engine should run very, very smoothly. I once had my engine running very smoothly but discovered that I had it advanced much too far. So use a timing light to start. If you have no pinging and the "water jar" doesn't wiggle, you've got it right.

If it runs smoothly but still diesels a bit after turning it off, or if you get some pinging, then try mid-grade gas. I've had to use it on my 8:1 rebuild almost from the time I had the engine installed.

Enjoy the new power!

Jeff

jp-
01-16-2007, 10:13 PM
I was always told to retard the timing til it almost dies, then advance until it almost dies, and set it in the middle...

Is this wrong?

This is assuming that you don't have a timing light handy.

Rod Turnbull
01-17-2007, 12:39 AM
Here is another fun way without a light... put on the E-break, put it in gear, have someone push down on the gas and break at the same time, so it is under load but not moving (when I'm alone I put it against a brick wall and use the throttle cable to, well, never mind)... advance it till it starts to ping and then turn it back just a bit till it stops.

When someone tries something stupid like I'm suggesting, don't be surprised if you run yourself over. Take that as my legal disclaimer.

Rod

Clive
01-17-2007, 06:57 AM
There are some great suggestions here - but I will reserve the Turnbull "Wall Technique" for the last resort and make sure I have someone videoing it for posterity!!

Meantime last night I set it to 3 deg ATDC - absolutely no power today, couldn't get above 40 mph even with the wind behind! But it ran smoothly and the water didn't shake. Using regular gas. Today I will set it at TDC and work up from there....and after exhausting timing options try the mid-range gas. Many thanks.

Rod Turnbull
01-17-2007, 08:01 AM
Did I mention the part about not standing between the Rover and the wall? :rolleyes:

Best of luck.
Rod

jp-
01-17-2007, 11:45 AM
Here is another fun way without a light... put on the E-break, put it in gear, have someone push down on the gas and break at the same time, so it is under load but not moving (when I'm alone I put it against a brick wall and use the throttle cable to, well, never mind)... advance it till it starts to ping and then turn it back just a bit till it stops.

When someone tries something stupid like I'm suggesting, don't be surprised if you run yourself over. Take that as my legal disclaimer.

Rod

Rod,

You can't load a stick shift the way you can an automatic. If you have it in gear and it's not moving, you're slipping the clutch. This is bad.

Jeff Aronson
01-17-2007, 05:01 PM
There are some great suggestions here - but I will reserve the Turnbull "Wall Technique" for the last resort and make sure I have someone videoing it for posterity!!

Meantime last night I set it to 3 deg ATDC - absolutely no power today, couldn't get above 40 mph even with the wind behind! But it ran smoothly and the water didn't shake. Using regular gas. Today I will set it at TDC and work up from there....and after exhausting timing options try the mid-range gas. Many thanks.

Umm, something doesn't sound right here. Before you touch the timing, have you gapped the points? Are they new and clean? This needs to happen before you consider changing the timing.

Jeff

Clive
01-18-2007, 07:04 AM
I have installed a Petronix electronic ignition (newer type Lucas distributor) so no points to adjust.....(unless I am missing something!) however, last night I set it to 3 deg BTDC with the light and I have a bunch more power today. Still doesn't feel as powerful as it should though.
Another question - when setting the timing with a light should I diconnect the vacuum hose and set it that way, then reconnect the hose and adjust idle to 750 rpm? Many thanks for all the input, it is getting better all the time!

singingcamel
01-18-2007, 10:16 AM
does it idle o.k.? how about when you revve the engine? any hesitation ?
if it idles ok without a noticable miss out the exhaust ,you should be close.
if there is no obstruction to the carb linkage, carb is set right, the next thing to do is pull plugs one at a time and check compression,125- 145 lbs/sq "if your down one one cylinder you may have dropped a valve (burnt) causing a loss of compression in one clyinder,causing poor preformance.(no power)

Clive
01-18-2007, 12:10 PM
Thanks. It seems to idle completely smoothly @750 rpm (set the mixture in a new Weber single barrel), and 3 deg BTDC. Takes a few turns of the motor to start when hot, and also runs on a bit after turning off.

When I rev it feels like there may be hesitation sometimes...but difficult to be sure as i don't have enough experience of this. What does hesitation mean?

Clive
01-19-2007, 06:47 AM
Compression is 160+ in all cylinders (8:1 head). Engine still diesels and doesn't backfire but definitely "burbles" on deceleration. No evident leaks around manifolds or pipe....

Bostonian1976
01-19-2007, 08:53 AM
you still definitely have timing issues according to your previous post (2 posts ago)

Clive
01-19-2007, 09:18 AM
Yep - I think there is still an issue - it does not seem to have the power an 8:1 head should. I've checked the brakes aren't dragging, and the T-brake. New Wber carb set to corect mix.
But everything checks out unless I try going to 6 deg BTDC or beyond? What sort of damage if I advance the timing too much?

Bostonian1976
01-19-2007, 09:55 AM
Yep - I think there is still an issue - it does not seem to have the power an 8:1 head should. I've checked the brakes aren't dragging, and the T-brake. New Wber carb set to corect mix.
But everything checks out unless I try going to 6 deg BTDC or beyond? What sort of damage if I advance the timing too much?

pretty sure you can just overheat (or is that too retarded?). I'm still newish to this stuff myself. Know what I did? Went and got a Pertronix distributor, some new plug wires for the hotter spark, timed it by ear, and everything has been perfect since......a very worthwhile 200 bucks in my opinion.....

singingcamel
01-19-2007, 09:59 AM
any vaccum leaks,also twist your rotor ,does it return ?
i agree,sure sounds like a timing issue but if youve done what you said you did ,it may something else.
points did you regap or replace them,i would,i agree with jeff . change out that rotor and condenser as well. inspect the dizzy cap for cracks.
you can't always go buy the book on these beast, especially if there has been work done on the engines,timing gear may no be on ,timing chain loose. keep going you'll find it and keep us posted..marc
www.singingcamel.com (http://www.singingcamel.com)

BackInA88
01-19-2007, 03:26 PM
I have installed a Petronix electronic ignition (newer type Lucas distributor) so no points to adjust.....(unless I am missing something!) however, last night I set it to 3 deg BTDC with the light and I have a bunch more power today. Still doesn't feel as powerful as it should though.
Another question - when setting the timing with a light should I diconnect the vacuum hose and set it that way, then reconnect the hose and adjust idle to 750 rpm? Many thanks for all the input, it is getting better all the time!

I was wondering the same thing about the vacuum hose.
"Back in the day" all my others cars had the timing set with the vacuum disconneted and plugged but I saw nothing in the crappy Haynes book about disconneting it?

I have a new Weber and a complete electronic distributor I got off Ebay with the timing set at 6 degrees.
I don't notice any pinging but it does run on a second when I shut it off.

I think my head is a 7:1 even though it is suppose to be a crate engine. The guy I bought it from said it had hardened valve seats.
I can't imagine buying a crate engine and not upgrading to 8:1?
I don't see the stamp on the head bolt boss across from the carb.

I am going to do a compression test on it.
What should I get if I have an 8:1 head with good rings and valves?

Can I just mill the head to get 8:1, if so how much comes off?

Can I just

dmurrell
01-19-2007, 04:46 PM
The reason to clamp off the vacuum line is to ensure there is no "vacuum advance" being applied to the distributor.

The thing to be careful of with Pertronix is the magnet is 90 degrees off from the lobe that used to open the points, so be sure to retard the ignition significantly berfore you start. Also, I'm a little detail oriented, so I typically use an old "dwell meter"

Best of Luck,
Dave

yorker
01-19-2007, 05:25 PM
http://www.lrfaq.org/Series/Engine.CylinderHead.html

I wouldn't really worry about making a 7:1 into a 8:1. if the 7:1 is in good shape the truck should run fine and have "plenty" of power. :D

BackInA88
01-19-2007, 06:45 PM
The reason to clamp off the vacuum line is to ensure there is no "vacuum advance" being applied to the distributor.

The thing to be careful of with Pertronix is the magnet is 90 degrees off from the lobe that used to open the points, so be sure to retard the ignition significantly berfore you start. Also, I'm a little detail oriented, so I typically use an old "dwell meter"

Best of Luck,
Dave

Dave,

I Know with passed vehicles there was always some vacuum advance even at idle, hence the reason for disconneting and plugging before setting the timing.
So your saying the vacuum advance hose on the 2.25 should be done the same or the hose clamped.
I am only double checking because the "cheap" manual I bought made no mention so I set the timing with it connected to vacuum.

Thanks
Steve

Clive
01-20-2007, 08:13 AM
OK - still not clear:

1. Should the vacuum hose be disconnected when setting timing with a Pertronix EI installed?

2. How do you know when the magnet is 90 deg? Er, 90 deg to what exactly? Sorry but I am really trying to figure thius out...and many thanks for the suggestions.

I believe an 8:1 head should have a compression of ~160.

yorker
01-20-2007, 08:50 AM
OK - still not clear:

1. Should the vacuum hose be disconnected when setting timing with a Pertronix EI installed?

2. How do you know when the magnet is 90 deg? Er, 90 deg to what exactly? Sorry but I am really trying to figure thius out...and many thanks for the suggestions.

I believe an 8:1 head should have a compression of ~160.

#1-yes Timing is always done with the Vacuum advance disconnected.
#2 IDK
#3 yes more or less~ there and even compression across all cyls within reason.

http://www.bayourovers.com/trick22.html pertronix install
http://www.bayourovers.com/trick19.html timing tricks

Clive
01-22-2007, 07:06 AM
Thanks Yorker, the motor is delivering a lot of power now, finally set at just over 6 deg BTDC! :thumb-up: And appears to run smoothly. Slopes that last week were a struggle in 4th I am now switching into overdrive before the crest!! Great feeling! :)
BTW, what is IDK?

yorker
01-22-2007, 04:23 PM
IDK = "I Don't Know":thumb-up:

it is one of those little shorthand things that seems to cropped up on the Internet like
IIRC= "If I Recall Correctly"
RKI= "Relatively Knowledgeable Individual" (as opposed to an expert)
YMMV="Your Mileage May Vary"

I'm glad you got your timing sorted out- I know how things like that can be very aggravating and it is easy to forget to unhook the vacuum advance.

singingcamel
01-23-2007, 02:31 PM
:thumb-up: thanks for the up date, this is how we all learn :thumb-up:

bchene
01-26-2007, 10:17 PM
I recently installed an electronic distributor and after some testing ended up at 6 degrees BTDC. Same as you. I also found a note that you do need to disconnect/plug the vacuum advance.