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

[Ren_RG28]

For those who are interested.. Just so you know NGK 18RG leads are still available in Australia. I remember seeing some on Ebay recently claiming to be a"rare item".

I purchased mine from Coventry Auto at Geebung (Brisbane) for $60 + $14.95 for an overnight air bag.

[o_man_ra23]

+rep for a part number Ren

[airfireman1]

You will have to remove the timing cover to remove the chains. Once the cover is off you can remove the top chain ,then the lower chain is removed as a unit with the sprockets.
So drop the sump and dont forget to check to make sure you have removed all the bolts. The bottom tensioner may spring out so no great drama but best to unbolt it first.
Cheers dave

[tricky]

Ren, what angle to the leads come out of the rocker cover on those items? I've heard some bitching and moaning spew forth about the leads coming straight up, potentially grounding out on the bonnet, like top gun make. I need some appropriate leads in the near future, and I'd love to not pay through my anus for custom items...

[o_man_ra23]

Tricky, every photo I have seen of the NGK items shows they have the right angle boots... I hope this is still correct is it Ren??

[Ren_RG28]

Tricky & O_man: NGK Spark Leads are the only aftermarket leads available for the 18R-G which have right-angle boots for the spark plug chamber. That's why I bought them, even though their insulation is thinner than Top Gun's.

Part No: RC-TE94 (I've got a pic uploaded on my Rebuild thread if you wanna see what they look like)

[tricky]

Awwww, shit yeah! Rep for that dude!

[airfireman1]

Well I am reaching the end of my patience with this 18rg swap. 3 or 4 things are still giving me the sh###. The timing chain is still noisy and the tensioner has started leaking oil. The leak can be fixed by replacing the 0 ring. The timing chain must have a ot of stretch a the adjuster is all the way in and I still have more than 2mm novement from the adjuster (outside the standard specs) I have what sounds like a noisy valve on cylinder no2, I am just hoping that it is not a sticky or slightly bent valve as that was the one that was open when the head was taken off and unfortunately bumped over and rested on the valve. That noise can be heard above the engine noise
I cant get a decent idle no matter what I do to the carbs, very hard to start when cold but starts very easily when warm.
It blows no smoke so the bottom end seems good.
The choices are remove head, drop sump and replace all timing gear refit recon head, go efi maybe as I have all the parts or
If I am going to replace the chains and guides and refit the cylinder head I may as well rebuild the 18rgu I have in pieces in my workshop that would mean getting the
cylinders honed,
getting the 18rgeu head fully rebuilt (been quoted $480 including welding,surfacing,and resetting vavle clearances.
I have a brand new set of 9.7 18rg pistons still in thier boxes so they will go in.
crankshaft probably needs a regrind hopefully just a linish but doesnt look all that good
new rings,bearings
I have new timing chains and reconditioned guides
Brand new 18rg exhaust camshaft still in box (how would that go coupled with a 18rgeu intake camshaft?)
Then ditch the solex's and refit all the fuel injection stuff
So cost wise it should look like this
cylinder hone - $50
head rebuild - $480
crankshaft regrind - $160
Rings - $58
Bearings - $140
I have all gakets already
I need your thoughts How does that sound for price? Thats a lot of dollars for an old 18rg series engine
thanks

[sillycar chick]

If the timing chain is noisey AND the tensioner is leaking, then yes you need to replace the oring, and once fixed the tensioner will build up pressure and stop the chain rattling. Do you have new chains and guides?

[o_man_ra23]

New top chain is $40, and there should be a breaker link on it. You should be able to replace the top chain without removing the head, takes a bit of swearing, and some coathanger wire, but quite possible (ive done it twice). As Sirrichik said, the oring will help stiffen up your tensioner which will help your rattles.

As for the valve, get a compression guage and check... easy enough to find a leaking valve (if its bent). If not, check how much pressure it takes to depress the valve with a screwdriver (levered) compared to the others, this will indicate a broken/strained valve spring.

[airfireman1]

thanks for the replys,
I have done a compresion check and there is a varience between cylinders of around 15lb. I do have new chains and guides/tensioners, they are reco ones and although the material seems a little harder than genuine I think they should be ok.
I have just dropped the 18rgeu head off at the cyl head reconditioners for a full rebuild. One question that I have is that there are two types of top tensioners, the short type that was fitted to the 18rgu head and the older looking long type that was fitted to the 18rgeu head. Are they interchangable? The guide that the tensioner pushes against has a different back.
I think I may remove this head and drop the sump and remove the front timing cover and replace both the top and bottom chain and also the guides and tensioners. I have a new set of chains that are rollmaster brand. and includes new lower sprockets
It will probably be easier if I pull the motor out again, not that I want to but it will allow easier access to the sump bolts.
I am still tempted to ditch the carbs and refit the efi even though it will probably mean more work.
Cheers

[sillycar chick]

You got the guides done through RAd's group buy didnt you? Yeah they are a lot harder than the stewart wilkins ones I have in my engine, they should guide the chain fine, but i was a bit sceptical about damping chains. They still should be fine though as long as you have new chains. The biggest problem will be that tensioner, mine was leaking and causing my engine to rattle even though i had new chains and steward wilkins guides!! Just be careful what oring size you get, theres a few different sizes listed in witzls thread, you have to make sure you get the right one or it can still leak or lose pressure. It took me a couple of goes to find one that didnt leak or rattle, and eventually it started to leak a little but hadnt rattle so i left it.

[airfireman1]

Thats right,although I do have a brand new genuine top guide and also the tensioner curved one but it has a different setup on the back side thats why I was asking about the different tensioners. If the chain is so stretched and worn that even though the tensioner is at or near its full adjustment the only sollution will be to put new chains in. I will try and rebuild the tensioner as it is dripping quite badly.

[o_man_ra23]

Dont forget to use rubber grease when installing the oring too.

[airfireman1]

Pulled apart the tensioner and the 0 ring is square so I am of to find a suitable replacement