I very much doubt the block is anything but a normal 2tg block - the 4ages
etc only have 4A on the block. It is the head and internals that makes the
difference.
On Fri, 9 Oct 2020, 11:00 robin romain, <robin.romain43@xxxxxxxxx> wrote:
Does anybody know if the fact that my engine number starts 2t and not 2tg
means it needs the oil feed mod you describe? And is there a way of
telling if its been done?
Or just stop worrying?.....
Rob
On Tue, 6 Oct 2020, 14:09 Mark Errington, <mam@xxxxxxxxxxxxx> wrote:
Hi Rob,
The 2TG with a Yamaha head is a brilliant motor. The carburetted
versions always went better than the injected ones. When the Group A
regulations first came out in the early ‘80s, I built up a Group A TE71
Corolla with this motor for NZ Rally Champs and Rally NZ. With forged
pistons, Suzuki motorcycle rings, blue printed carbs and Lotus cams, it
would pull strongly to 9,000 rpm. Ultimately, this was my undoing! On a
twilight stage in the Coromandel, I was sitting on 9,000 rpm up a long
straight uphill in 3rd gear to a flying finish just over a crest.
Perhaps we got a little airborne over the crest. As we completed the time
cards in control, I noticed a very rough idle. I then noticed a youth
running up the road out of the stage. At the drivers window, he presented
me with a big end. I knew it was mine, as I had personally linished them
all to a high standard. It was still a very rough idle. By torch light,
we could see bearing shells on the sump guard and that the last 6 inches of
the sump had gone. The rings on #4 piston were visible through the rear
frost plug, at a 45 degree angle to the bore. It was still idling very
roughly! We limped down to the next intersection and switched it off.
We reblocked that engine using a single cam 2T block. We salvaged the
crank and I recall the rebuild was straightforward. After 35 years, I’m a
little vague on the details, but I recall that the single cam came out and
a short jack shaft from the twin cam motor went in to drive the distributor
and oil pump. I do recall we needed to block off an oil feed that had
originally feed oil to the rear of the single cam.
Having drafted this, and paused for lunch and a short nap, I googled the
problem. (Google was never part of the original toolkit!) This suggests
I’m on the right track:
https://www.toymods.org.au/forums/threads/55946-2TG-head-on-2t
Cheers,
Mark
021 334 612
PS: That big end still sits on a high shelf looking down on the kit car
build.
*From:* ccc-qna-bounce@xxxxxxxxxxxxx <ccc-qna-bounce@xxxxxxxxxxxxx> *On
Behalf Of *robin romain
*Sent:* Tuesday, 6 October 2020 8:38 a.m.
*To:* CCC-QnA@xxxxxxxxxxxxx
*Subject:* [ccc-qna] 2tg motor
Hello to all....I am Rob Romain and l own a Chevron seven .l enclose a
photo.
The problem I would like members advice on is my lack of oil pressure. It
does not reach 40 psi until about 4000 RPM. And very little on idle, even
when cold. The oil pump looks good, the gauge is confirmed as accurate, and
new oil and filter are installed. One workshop I took the car to put in new
big end shells , saying the old ones were poor. They said they could
Not obtain new main shells but said the old ones were serviceable. A
plate on the cylinder head says 2tgeu. This cannot be true since the EU
stands for fuel injection which it isn't.
The engine block is stamped with the number 2T 813 7415.... could this
mean that the block was originally from a 2t engine which was converted to
2tg? And that during the conversion something was left out which causes the
pressure to be lost.?
Any help would be wonderfully welcome. Rob
