Gamijectors - problem probably solved

I sent the following note to the Cardinal Flyers Online. I repeat it
here in case it may help somebody, or if anybody has advice!

Here is an update on the problem I was having getting my Gamijectors
tuned on my engine. As I posted in #3311 in September, I had done a lean
test that indicated #2 was peaking at the lowest fuel flow and a spread
of 0.7 gph. John-Paul at Gami said great, we’ll get you a leaner #2 and
it was installed. Then the next lean test indicated that #2 had actually
gotten a little worse, with a spread of 0.8 gph.

There followed some discussion in digest #3314 with Paul and George
Braly that suggested investigating #2 for other problems such as
induction leak or cam lobe wear. Well, I finally got it into the shop on
Friday. First thing the AME did was measure the intake valve lift. He
compared #4 at 0.46 with #2 which was 0.25. So off came the cylinder and
what do you know? The #2 lifter has failed in such a way as to make it
pound against the cam lobe, which in turn is badly damaged. The camshaft
is ruined and my engine goes to Progressive in Kamloops this week for
teardown and repair.

This may explain a lot. Cylinders 1 and 2 share the same damaged cam
lobe for the intake values, so I believe both those cylinders have been
producing less power. CHT on #1 and #2 have always been significantly
less than #3 and #4; I assumed this was because they got more airflow.
The engine has always run smoothly.

This aircraft cruises at 130 knots or maybe slightly more. The previous
owner thought this was normal, but it has concerned me ever since I
started reading this digest and discovered most RG owners claim 140+
knots cruise, which of course is what the book says too. The flaps were
badly out of rig, but fixing this made little difference. The other
controls have been carefully re-rigged as well. Nothing has helped in a
significant way. The only other thing that should cause this is a lack
of power, but I always got full RPM and MP. Should have had the camshaft
checked a long time ago...

Cost to split the case and repair is C$6k (Canadian and US dollars are
about equal at this time). An additional $1k gets a bottom overhaul
accomplished, so this is a no-brainer. My engine is 750 hours and 13
years SMOH and this will zero the bottom end.

I have a few decisions to make. First, should I get the Firewall Forward
camshaft with built-in lubrication? Sounds like a good idea.

While the engine is off this may be a good time to get the Firewall
Forward Horsepower Plus STC. I’ve searched the digest and people seem to
be pretty happy with it. My only concern is oil temperature – mine goes
into the 220’s on a hot day (CHT’s are under 380.) The FF oil cooler STC
was installed this summer which helped a little but not much. The
Vernatherm also came off on Friday and there is some visible damage
where it seats. This will be machined and fixed. However, I’m not sure I
want to put the FF pistons in before I have solved the oil temperature
problem. This is a bit of a conundrum. Any suggestions?

One last thing. When the cam has been repaired should I continue to use
the existing Gamijectors that are currently installed? They have been
tuned for the engine in its slightly defective state. #1 and #2 may no
longer be appropriate.


randall g =%^) PPASEL+Night 1974 Cardinal RG
http://www.telemark.net/randallg
Lots of aerial photographs of British Columbia at:
http://www.telemark.net/randallg/photos.htm
Vancouver's famous Kat Kam: http://www.katkam.ca