For the love of a tractor engine: The life and times of the 18R-G

[o_man_ra23]

The cams are meant to have a fair amount of overlap, this can give you the backfire and the hard to start bit. You may have slightly too much overlap. Retard the cams as much as you can by tightening the tensioner when setting their timing. If you run out of holes, slip a tooth, and pick a different hole

[airfireman1]

I think I may try that, i will recheck the cam timing again tomorrow. i think they are now too far advanced. I have a dreaded timing chain rattle at start up and the tensioner may be at fault. Its hard to pinpoint the bad idle down to a single thing. Until I am sure that the cam timing is spot on. I think also the carbs are not helping.
Just a thought and i will run this by all in the know. As every body knows, you cannot run the balance tube on the short manifold when using webers due to the choke mechanism being in the wrong location. If I removed the studs from the manifold and replaced them with longer ones, then used a spacer block to clear the balance tube. Would that be a easy solution to fitting the webers? then I could get rid of the solex's
cheers

[o_man_ra23]

What about the early type of manifold with the flexible connections to a tubular balance tube??

Also, before you can play with carbies, you need to get every mechanical setting right. So re-check your cam timing (you can tighten up the tensioner, keep going till it stops rattling and starts whizzing, then back it off a touch) and dizzy timing etc. Also the timing tensioners have an o-ring in them you can renew to try and help, plus being a hydraulic item, the chain will rattle until you have sufficient oil pressure to operate the tensioner... so I think your pretty well stuck with that one unless you replace all your chains etc and give the whole thing an overhaul.

[airfireman1]

I will redo all the settings again. I have what I think is a noisy valve, possibly the clearance is out but it may also be a sticky valve. The reason I am leaning this way is that the head was removed with the cams on and placed face down on a work bench and I have read where the valves bend very easily when this has happened. That would lend a lot of creedance to the poor idle and very lumpy progression from idle to about 2000rpm If I have no joy then I may pull the engine out and take the head off again and pull the timing cover and replace the cam chains. That way I know that they are not stretched. When you think about it, it is quite a long chain and wear and stretch could easily make it difficult to take up all that slack. After all its only about 1 hour and a bit to remove the motor, then a couple of hours to strip it and replace the chains, then,head on and refit, another couple of hours. Then I know its all good.
Thanks for the replys

[o_man_ra23]

Compression test will reveal a bent valve quite quickly, feeler guages will reveal incorrect clearance, and a light tap with a hammer and length of wood on the tops of the buckets should tell you if any of the valves are sticky (they will have more of a thud noise than the others)

Good luck finding the cause of the problem.

[airfireman1]

Its amazing what 24 hours will do!!!. I have just finished a 14 hour night shift and even though very tired I decided to go up to my workshop and have another play at the motor.
With some success, the timing chain rattle was due to too much tension. I backed it off and its very quiet now.
On to the carbies, I have got them balanced as best I can without a balancer. And the idle is way smoother and there is very little imbalance when the revs are slowly applied. I think most of the problems are balance related and I will try and hunt up a balancer on egay. I will take it for e test drive after a sleep.
Cheers

[o_man_ra23]

What I did for a balancer was get 2 commodore vacuum guages (economy guages) and mounted them side by side on a board. You need to 'calibrate' them so that they both read the same signal. Easily done, start the motor, warm it up, let it idle, then attach one guage, record the reading, attach the other guage and fiddle with the pointer till it reads the same. Then you should put one guage on each carby, and balance them... then you can play with the mix properly. Pretty cheap balance guage, considering most wreckers will just about give away economy guages.

[hosking1991]

Hey guys,

I got a price for a pair of top gun leads for the rg 60 bucks. Has anybody had experience with top gun leads for the 18rg?

cheers

[Gttwinturbomk3]

Hey guys,

I got a price for a pair of top gun leads for the rg 60 bucks. Has anybody had experience with top gun leads for the 18rg?

cheers

Yeah mate...

A friend of mine fitted them on to his 18rgu, the size was 8.8mm leads that he had not the 10mm ones. The 10mm ones are a bit too big. He hasnt had any problems with them. They are good leads, and are worth getting to dress up the engine bay a bit as well

[airfireman1]

As above,the only down side is that the leadscome straight up instead of at right angles to the cap.
Cheers

[EldarO]

Elmo, what car are you going to fit the 18rg into?
Well after another day in my workshop, Webers were removed as they were running way too rich. I overhauled a set of solex's and fitted them along with puting the balance tube back on. Rechecked and adjusted the cam timing, made a throttle linkage set to use the original pedal. It runs much better and revs very freely and linkages allow full range of movement
Cheers.

missed this, my bad.

was supposed to be turbo'd and put into my TA22, but couldnt keep the car so the motor has to go too

[airfireman1]

Did you end up selling it then?

[o_man_ra23]

I used to run the 8mm Topgun leads, they were great. Cost $44 from Autobarf. As mentioned though, the non-right angled leads were poo, and from memory the coil lead that came with it was about a mile long.

And Elmo, as Airfireman said... you sold the motor yet?? I am currently looking at options for turbo 18R'ing my RA28

[RAd28]

Quick 10 Pointer to anyone with a pair of 18RG cams handy......

what does a pair of cams weight? to the nearest whole KG preferably

cheers

[hosking1991]

Quick 10 Pointer to anyone with a pair of 18RG cams handy......

what does a pair of cams weight? to the nearest whole KG preferably

cheers

i'll get back to you tommorow mate sleep time first good night