CairB
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| posted on 3/4/08 at 07:01 PM |
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Just a thought.
Backlash in the VVT mechanism, not the valve, may show up if the engine is manually turned over with the cam cover off.
Check whether the inlet cam jumps relative to the cam drive when the valve springs try to push the cam forward.
I was involved with variabale valve timing back in the mid 80's and it still sounds to me like cam drive backlash.
I hope you find the culprit soon.
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sgraber
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| posted on 3/4/08 at 07:13 PM |
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I will do this observation on the vvt gear.
I should be able to hear this 'clack' if I were to remove the valve cover, remove the plugs and crank the engine. It would be the same
volume if the cover were on or off right?
One clue from yesterday I forgot to mention -- when I was priming/cranking the engine with the plugs out; from inside the #4 cyl plug hole I kept
hearing a strange thwunk as the piston would switch directions up and down. tdc/bdc ... A hollow thwunk - like someone slapping the open end of a
glass bottle with their open palm. But it went away after a bit of cranking. The engine started up and ran silent, but only after about 10 seconds the
clatter sound came on again and just got louder.
quote:
Originally posted by CairB
Just a thought.
Backlash in the VVT mechanism, not the valve, may show up if the engine is manually turned over with the cam cover off.
Check whether the inlet cam jumps relative to the cam drive when the valve springs try to push the cam forward.
I was involved with variabale valve timing back in the mid 80's and it still sounds to me like cam drive backlash.
I hope you find the culprit soon.
[Edited on 4/3/08 by sgraber]
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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MikeRJ
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| posted on 4/4/08 at 09:12 AM |
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quote:
Originally posted by sgraber
One clue from yesterday I forgot to mention -- when I was priming/cranking the engine with the plugs out; from inside the #4 cyl plug hole I kept
hearing a strange thwunk as the piston would switch directions up and down. tdc/bdc ... A hollow thwunk - like someone slapping the open end of a
glass bottle with their open palm. But it went away after a bit of cranking.
I don't like to suggest such nasty things, but perhaps a piston has a broken skirt? This would cause it to rock in the bore and make rattling
noises. I hope not though, and it only takes a little bit of piston slap to make a ticking noise TDC when you turn an engine over manualy so fingers
crossed.
OTOH the compressions do look low, I wonder if you could just possibly be seeing the effects of sticking valves? That would certainly make things
noisy.
[Edited on 4/4/08 by MikeRJ]
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sgraber
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| posted on 4/4/08 at 01:20 PM |
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I took the head off and the problem became evident pretty quickly.
First off there is some deep scoring in #4:
Next is the piece of metal welded to the top of the cylinder wall in #3, along with some horrible scoring and piston damage:
But the crowning glory has got to be the fact that when you rotate the crank the #4 piston has about 1/2" of slop before it moves up or down! I
took a video but I can't even bring myself to post it up.
Top it off with the almost certain knowledge that the vvt pulley is bad and that there are flecks of aluminum galling off the cam bearings and
it's easy to believe that this engine was abused at some point before I got it.
It's almost unbelievable to me that someone would and try to pass this piece of ____ off as a usable engine. I unfortunately left him good
feedback on eBay before I tried to start it up. Of course he will claim that he didn't know about this damage... So what can I do but take it
like a man and move on?
To me it seems like it's not worth the effort of rebuilding.
Damn it I am pissed as hell right now. 
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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jollygreengiant
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| posted on 4/4/08 at 04:17 PM |
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Steve you have my sympathies.
A company local to me sold me parts for an early cross flow when I explicitly told them it was for the later cross flow. When I suffered engine
failure as a result they refused to do anything about it because 'I had not given them a written order'
I don't hold grudges
much
oh it was SHELLTUNE of Northampton.
Never used them since.
Beware of the Goldfish in the tulip mines. The ONLY defence against them is smoking peanut butter sandwiches.
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MikeRJ
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| posted on 4/4/08 at 04:19 PM |
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Not good news
The markings on no.4 suggest to me that it's been sat full of water at some stage.
I sort of know how you feel as I bought my current car from Ebay and advertised as "sometimes smokes a bit". As it was a turbo I figured
the seals were on their way out. Turns out "a bit" actually meant "completely obliterates the road behind you", and the cause
was a melted piston...
I think you just have to believe that the laws of Karma will eventually catch up with them.
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sgraber
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| posted on 4/4/08 at 04:26 PM |
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Here's a video of a piston that does not move or play well with others.
http://www.youtube.com/watch?v=lz3zptp-GjM
I will take this and chalk it up to experience.
What I have learned (along this entire car project) is that you should not always try to go for the least expensive solution. I have spent more time
trying to fix engines than I have driving the car.
Next engine will be thoroughly checked out and I think I'll go for something with 200bhp! Just to make me feel better.
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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jollygreengiant
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| posted on 4/4/08 at 04:39 PM |
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Beware of the Goldfish in the tulip mines. The ONLY defence against them is smoking peanut butter sandwiches.
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CairB
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| posted on 4/4/08 at 08:51 PM |
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Sorry to see the damage, at least you can move on now. Whatever the problem it's always better to know.
No 4 does look like it has had water damage.
I once had a bike engine with a broken gudgeon or wrist pin that had similar movement.
What engine are you thinking of using next?
Commiserations,
Colin
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MikeRJ
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| posted on 4/4/08 at 10:21 PM |
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Hmm, evidence of water in the bores and what could be a broken piston or gudgeon pin. What are the chances this engine has sucked in water and been
hydraulically locked at some time in it's past?
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Mark G
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| posted on 4/4/08 at 10:43 PM |
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looks that way, hydrauliced engine and snapped pin.
would it be cheaper to get a rebore and over sized pistons instead of replacing the engine with something else.
I'm just thinking of everything else that goes with the engine. G/Box, Loom, Time, Effort???
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triumphdave
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| posted on 5/4/08 at 09:36 AM |
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quote:
Originally posted by Mark G
looks that way, hydrauliced engine and snapped pin.
would it be cheaper to get a rebore and over sized pistons instead of replacing the engine with something else.
I'm just thinking of everything else that goes with the engine. G/Box, Loom, Time, Effort???
And of course there is no guarantee the next one wont be a lemon also.
If you always do what you have always done you will always get what you have always got
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thomas4age
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| posted on 5/4/08 at 02:01 PM |
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Ah shit! hate to see that happen.
looks like, the headgasket had been blown at some point in it's life and the owner has carried on running the engine afterwards, left it
overnight, and started it up the following morning,
I have just fixxed a toyota starlet which has exactly the same problem.
the starting with the cold engine with the cylinder filled up with water has caused hydraulic lock which took the rods and bearings......
eaahuummmmm probably.
the problem with the VVT gear is btw not the valve, but a little backlash in the gears in the camsahft pully, the clatter a tiny bit on idle, almost
every vvt engine I have heard does that, the sound is very little.
I have had one Valve failure, it was stuck close so the timing wouldnt advance, making it a very smooth but dull engine but still drivable.
Good luck and don't give up on them, once it's right the 20v is a very nice engine to have.
last years result in the engine demolishing sequence is
6 broken honda's vs 1 broken 4age,
so think again when going the honda route
Grtz Thomas
[Edited on 5/4/08 by thomas4age]
If Lucas made guns, Wars wouldn't start either.
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sgraber
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| posted on 5/4/08 at 02:43 PM |
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I have to agree about the hydro-lock. It seems very plausible. The head gasket does look almost new. Very shiny, no rust marks or mineral traces, but
why would they put a new hg on and leave the bottom end messed up? Were I not going to repair the engine I would have put the old one back on?
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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thomas4age
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| posted on 5/4/08 at 02:46 PM |
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looks like they fitted a new gasket to sell the engine off and be done with it perhaps.....
by looking at the orange gasket inserts the engine has never been run with this headgasket.
I have seen a lot of engines being sold good and on first inspection reveling all sorts of isues, my first 20v Silvertop spun a bearing but was neatly
replaced under waranty.
grtz Thomas
[Edited on 5/4/08 by thomas4age]
If Lucas made guns, Wars wouldn't start either.
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sgraber
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| posted on 5/4/08 at 05:32 PM |
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#4 piston and rod on the left, #3 on the right:
There is no bearing material at all left in #4. The bearing surface itself is gouged and pitted. The big end is also bent enough that I can't
replace the cap.
In addition, all 4 pistons have cracked ring lands and stuck rings.
The crank at #4 end:
I see a piece of the #4 bearing embedded in the crank, but there are huge divots in the steel surface. In addition, the crank does not spin freely,
indicating some other problem on the mains.
I am not going to bother taking it apart further.
The block might be salvaged, but is it even worth it when I can buy another motor with warranty for 500 of your UKP?
I do have one final option. Put the 20v head on top of my 3-rib early 4AGE short block. The pistons and bearings need replacing on that engine, but I
understand that it will all fit together. Unfortunately it becomes an interference motor due to the valve flycuts on the pistons not matching.
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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thomas4age
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| posted on 5/4/08 at 05:44 PM |
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IIRC the oil returns don't line up on a 3rib and a 20v head. also take note that the 3 rib has an oil pump with much less oompf than a 20v has
and most probably needs in order to lube the 4 extra valves and operate the VVT system.
The 20V pistons(42mm main) don't fit the rods in a (40mm) crank 3rib bottom end wristpins are of different desing also. using 16v pistons is
most likley to give trouble with interferance.
basicly the awnser is: Don't!
better to rebuild the Gen1 and pay hasselgren to do the headwork...... should yield much more power than a stock 20v-st
looking at the internals and the amount of damage I'd say the engine has been turbocharged in a previous life and has a very bad tune.... the
ringlands seem damaged to quite an extend right?
try to get a fresh 20v from japan through a know engine impoter that carries start-up waranty, have a look on ebay there's about 5 at the moment
at less then $900,- with waranty offered in the USA.
Other option to do is build a hybrid, 7age 20V with paradise racing pistons or the like....... looking at 180 to a 190 hp in that.
Grtz Thomas
[Edited on 5/4/08 by thomas4age]
[Edited on 5/4/08 by thomas4age]
If Lucas made guns, Wars wouldn't start either.
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sgraber
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| posted on 1/5/08 at 10:45 PM |
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I did buy a new engine from a reputable reseller on ebay. A blacktop 20v 4age with complete wiring harness and transaxle. It arrived recently and I
immediately tore it apart to check it out. It's in fantastic shape and I just can't wait to get it into the car. 
Thanks for all the opinions.
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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