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GM 3.6 VVT

So Cloyes called me back and said they couldn't help me with any further info. They suggested I do a return for the whole kit and that if I was a shop I could get some labor as well. When I go to RA website they want to break the kit down into individual components to warranty. I called Cloyes back and he gave me a number to talk to at RA but of course no one was there just had to leave a voicemail. Getting to the point that I'm seriously considering not doing business with RA anymore, lower prices (sometimes) isn't worth the hassle. Plus they're shipping to AK has gone way up mostly because they're warehouses won't use the PO most of the time anymore.
 
So here's my latest theory as crazy as it sounds. I think the primary tensioner is failing and it allowed the chain to climb the teeth on the crank gear and bend the valves slightly. Then it fell back in the right spot and the engine ran on the lower compression until I shut it off. Then the compression was too low to start. I've checked pretty much every way I can think of and the timing is right.
 
So I disassembled things,never did find a smoking gun on the timing. The tensioner plungers do have a sort of ratchet mechanism in them but I know the primary one moved at least 1/4" so either it hadn't gotten far enough out to engage or it wasn't working right. As I suspected when I disassembled the intake side of one heads the valves were ever so slightly bent.
 
Umm there is no hole in the cover. There's a dot on the crank gear and then 2 dots on the oil pump. One dot is a about 5 o'clock and that is the stage one timing position. There's another do at about 8 o'clock and that is the stage two position
 
So I gave up on RA returning my call. Left 2 voicemails with the guy and even tried the receptionist to see if he was out of town or something. Just a voicemail there too. So Cloyes is letting me return the timing kit to them, I mailed it to them today with about $1000 worth of insurance in case it gets lost. Also ordered valves and a head gasket set. In the hurry up and wait mode now
 
Could it be a set of weak intake valve springs, allowing them to float at higher rpm, that was the cause of contact and bending? Can you test them to see how many lbs they are at the maximum lift compared to spec?

Yeah, I've lost a lot of confidence in RA as I've been able to 1) find the identical parts from other on-line sources at overall lower cost when you factor that source's free shipping vs. RA's sometimes ridiculous shipping prices and 2) RA's non-availability of certain brand name items (like a complete set of KYB struts for vehicles) for extended periods (like 2 years) and not being able to take advantage of Mfr sale offers by buying a complete set of 4.
 
But. . . Spinning tires on ice/snow or in mud, a brief excursion beyond redline - jus' sayin'. Not questioning your daughter's driving habits, but we both know sheet happens we don't intend.

Were the valve springs new or reused when you built the engine? I mean the evidence is there in the fact that all intake valves are bent. Engine and cam timing is correct, you've verified that. The odds that the Cloyes VVT actuators are faulty are slim to none - factory engineers just don't design their motors to hit valves if the VVT fails at full advance or retard (now, if a timing belt breaks is a whole other story, Honda) - unless somehow RA's drop shipper's warehouse had somehow gotten ahold of some CKO fake branded crap and sold it as Cloyes.

Which leaves the intake valves floating as the cause of all of them being bent at the same time. Two things come to mind that makes valves float - too many RPMS or weak springs. If your theory of weak/non-op tensioner allowed the chain to climb on top of the crank gear and then drop back into time being the cause, then why no exhaust valves bent on either head, as that chain, from looking at the routing diagram, would have to had to put those cams out of time, too. And such an occurrence would certainly show up as abnormal wear/damage to the tops of the gear teeth as well as possibly to the chain rollers, too.

Not arguing with you, just running reasonable scenarios past you.

While you have the engine apart, checking the intake spring compression specs is easy to do.
 
IMG_20221128_163647.jpg
These I believe are supposed to ratchet. As the chain wears the ratchet engages to keep them from bleeding back and leaving too much slack. As far as exhaust valves I'm not surprised there aren't any bent ones. As the intake valves get closer to making contact the exhaust should be getting further away. If I can find the specs I'll check a spring or two
 
What I know of ...When you shut off the engine (known for some engines to jump time during shutdown) or the cam lobe from a closing valve spring tension "advances" the camshaft is the only real way to bend a intake from timing chain problems. My favorite way to bend intake valves is the WarWagon Worm clamp left in the intake port award... :facepalm: It's more exciting to watch the tach overspeed bend them...

Can the main chain tensioner bind up, stretch the chain, and in doing so advance the valve timing?

Machined the keyway in slightly wrong location on a sprocket? I rejected one timing set on the 1992 project as the chain went slack and tight as the engine spun by hand. I thought it might be a bent crankshaft so I put a magnetic dial indicator on it. Sprockets were machined off center.

Again taking two clues - prior rod bearing ...

Rod and other engine bearings can be damaged from excessive RPM. Aircraft piston engines are known for this in writing to teardown and inspect after X seconds over X RPM. My first failed engine a 1993 4.3L V6 was claimed to be bearing damage from the transmission slipping as it had slipped to burn up two weeks before engine bearings turned the oil to glitter. Independent shop suggested there wasn't an RPM limiter in gear for that year.

Is the transmission via ECM/Wiring problems downshifting into the wrong gear or shift flair (slipping or without enough TQ management)?

How are the wrist pins? Do you have stretched rods and/or rod bolts?

Valve guides gummed up scored up or *gasp* wrong too thick oil used in the cold? Yeah yeah here it's too thin of oil in extreme heat...
 
IMG_20221201_125038.jpg
So I checked a spring and the closed position is a couple of pounds low but the open height was right there. Scale needs cleaned and adjusted but should be close.
Haven't opened up the bottom end and am not inclined to do so. Don't know much about it's history as engine was bad when I bought it. Got new bearings when I put it back together somewhere around 3.5-4k miles ago. Other than me flogging it when I was breaking it in it's been driven fairly easily. I took it up to 7k but it wasn't a tire spinning quick rev but a controlled heavy acceleration and back off at redline.
 
ak diesel driver said:
View attachment 77997
So I checked a spring and the closed position is a couple of pounds low but the open height was right there. Scale needs cleaned and adjusted but should be close.
Haven't opened up the bottom end and am not inclined to do so. Don't know much about it's history as engine was bad when I bought it. Got new bearings when I put it back together somewhere around 3.5-4k miles ago. Other than me flogging it when I was breaking it in it's been driven fairly easily. I took it up to 7k but it wasn't a tire spinning quick rev but a controlled heavy acceleration and back off at redline.
Click to expand...
7,000 would make me pucker
 
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