Tim, some others on the list mentioned that the rocker shaft should have
already been removed, so the valve timing should not be an issue. Of
course, they are right, I dont know what I was thinking, but anyway you
shouldn't have a problem with the rope. When you think about it, you
probably have to really exert a lot of force to bend a conn rod or
damage a bearing, and I dont think that will happen during the process
of trying to break your head free with the relatively soft rope. But go
slowly anyway, and if youre really concerned try putting the same amount
of rope in the two cylinders that are going up towards TDC together (I'm
not sure which ones they are, but ISTR 1 and 6). That should distribute
the load. John
-----Original Message-----
From: Lumia, John
Sent: Thursday, March 20, 2003 8:59 AM
To: 'tjh173@yahoo.com'; '6pack'
Subject: Re: Rope Trick
Tim, I used the rope trick on my engine with no problem, and it
worked great. I think its probably best if you do it with the cylinder
of choice going into TDC between the compression stroke and power
stroke. This way both valves for that cylinder are closed and you wont
do any damage to the valve train. You dont need the starter, the crank
bolt works fine. Of course you need to remove the fan, the crank bolt
should be easily accesible. I was amazed on how little effort it took
to get mine off using this method. I used 1/2" yellow poly rope, but
almost any decent rope should work.
John - 1976 TR6
Tim wrote:
So I'm thinking I'll try the rope trick. Quick question: when doing
this, is it okay to use the starter motor to crank the engine over and
pop the head off, or is it better to just turn the engine by hand using
a long wrench on the crank bolt? I'd rather use the starter if
possible since it will generate a lot of torque, and since the crank
bolt is hard to get at. But I'm wondering if any damage could be
inflicted on the pistons or crank by the forces generated by the
starter when the rope gets compressed and the pistons continue to go up
and attempt to push the head off. I realize the pistons and crank
experience tremendous forces during normal running, but something about
this rope trick seems to suggest to me that it could inflict some harm
on the pistons. If the head is really stuck, then the pistons might
try to come up and get stopped dead in their tracks by the stuck head.
This is almost comparable to having the timing chain break and the
piston contact a valve, except that the piston is moving slower than
during normal running, and the rope is a lot softer than a valve. But
still, it seems a bit traumatic. Am I being ridiculously
over-cautious? Have other listers used the starter with the rope
trick, or just manually cranked the engine over with the crank bolt?
Tim Holbrook
1971 TR6
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