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Caming and timing issues.

Re: Caming and timing issues.

Postby tsuintx » Aug 13 2020, 5:05pm

Good to hear you found the issue and luckily it wasn't a biggie. Next time, might be good idea to go to bed before 3am. :mrgreen:
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Re: Caming and timing issues.

Postby DeltaZ71 [OP] » Aug 19 2020, 2:52am

EaOutlaw1969 wrote:Your right about the having to pull the heads to pull the lifters and the plastic lifter trays while doing a AFM delete, I may be wrong but the cam should be able to be pulled without pulling the heads just like the LS by rotating the cam pushing the lifters up then putting in a wooden dowel through the front of the engine or even using small pen magnets and clamps to hold the lifters up.
This is where miscommunication or the unknown can cause issues even if the issue does not cause interference between the valve and piston.
I know the following is splitting hairs but lets just say your engine overheated one day blowing one head gasket and only that one head was pulled and machined and a valve job done now you come along and do a DOD delete sending both heads off to get machined and another valve job now you can end up with one cylinder head with reduced combustion chamber volume, higher compression and varying installed valve stem heights.
Normally a good machine shop can keep you out of trouble if something like this happens by recommending different thickness head gaskets replacing previously cut valves and seats as needed to create a uniform within specification installed valve stem height and within specification push rod length.yet you have to catch your machinist on a good day and on top of his or her game and find one that cares about your engines performance and their reputation.
Even if the difference is minimal you have a high compression engine a stage two cam because you wanted the added lift and duration of your new cam but you do not want to end up with too much or too little lift. so it is worth checking these measurements for each cylinder and making corrections as needed for reliability and performance. None of the above in my opinion can be predetermined by a parts counter person even if they are a machinist unless they have tapped into some sort of Voodoo that I am unaware of.
Remember I am green with these engines and learning anything I can. but on any engine I have ever built or sent out for machine work I have found it is best to double check the work of others since their bad day at work will cost you more than it cost them every time. Below is just one example of why I try not to count on other peoples work.

As far as the Cam phaser do not be too hard on yourself at least you found the main issue before it caused real damage.

Back in the day we used to buy rebuilt Engines from ATK mainly because of their warranty that covered parts and labor which we only had to use once.
My Boss at the time now EX Boss and EX Father in law thought he would try out a new engine builder out of Miami after meeting the owner at a bar.
The first engine we bought was for a 1980s Bronco 2 a 2.8 liter I think which one of my co workers a competent new hire got stuck with the job.
The engine we bought was a long block at 600 bucks less than ATK we all gathered around for the start up after the install was complete I remember leaning over the fender watching the new guy pour in the coolant only to notice he had to put way too much in, I started to get nervous then my nervousness turned into panic when I noticed coolant pouring out of a vacuum line that had not been connected yet.
We knew immediately this engine was junk it either had a cracked head or wrong head gasket some thing very serious was wrong. So we called the supplier explained what we found. The new tech was once again tasked to swap the engine ( at warranty labor rate which sucked )
The second rebuilt engine showed up this time right away we spotted most of the the 12 point head bolts were rounded off!! We were pissed that this new supplier would actually ship out an engine this way ( how could have the bolts been torqued properly?) This is when they sent out a third engine!!
So with the new engine inspected head bolts were good on this one the new tech installed it once again we gathered around waiting to hear it run. with a turn of the key after priming the oil pump and setting the timing the engine fired right up but this engine had a rod knock.
Now everyone in the shop is furious yet desperate at this point to get the truck back to the customer. My Father in law decided two turn two of these engines into one good engine at least we hoped. We pulled the heads off of the rod knocking engine and used the short block off of the other engine since we did not trust the heads were not cracked. The new tech was once again tasked to swap the engine over.
When he was done with the install and ready to fire it up we all all gathered around again and were ready to celebrate and go have some beers when it started up with a weird scrapping rattling noise coming from the front timing cover area that lasted 2-3 seconds then the noise was gone.
Hoping it was a starter dragging and the noise traveling we all checked over the new techs install and found nothing unusual. so I went back to work on my work load of vehicles for the day. when I noticed the new guy and my father in law arguing in the parking lot while pushing the Bronco.
I went out there and calmed them both down and volunteered to take on the Bronco myself. Apparently it lost power and died on the test drive just making it back to the shop. My Father in Law was convinced he did something wrong when I stepped in and told him I inspected most of the install and he could not have caused this.
After looking it over I found about 75 PSi compression across the board remembering the noise at start up I pulled the timing chain cover to find the timing gear and chain had rubbed the cover, turns out when they installed the cam they put it in right but when they installed the cam gear it was 180 out this put the alignment pin 180 out it went unnoticed then they just drove the cam bolt or bolts home with an impact. On the test drive the cam gear worked its way loose loosing compression.
After a timing chain and gear set and timing cover was installed plus 3 back to back oil changes the truck was finally done But since we had no faith in it we offered the customer a brand new ATK engine at no extra charge but he would have to wait or he could take his chance with the engine in the truck at no charge and no warranty.
He opted the free route and remained a good customer never having another issue with that engine.
The point of all of all this is mistakes happen and even seasoned technicians looking for problems can overlook the obvious. Anyone of us that looked over the short block carefully should have noticed the dots on the cam and crank gears not being in the position they were supposed to be in and the cam gear being cocked at an angle. After this mess we exclusively used ATK regardless of our profit margin.
Holy sh!t what a freaking nightmare.... lol I had my fair share of nightmare cars when I used to work in the dealership, but even with my experience every once in a while I make some stupid mistake that makes me wonder what the hell was I thinking. Lol but thanks for sharing that man, it made me feel better.

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Re: Caming and timing issues.

Postby DeltaZ71 [OP] » Aug 19 2020, 2:57am

tsuintx wrote:Good to hear you found the issue and luckily it wasn't a biggie. Next time, might be good idea to go to bed before 3am. :mrgreen:
Yeah I'm never doing engine work that late again... grunt work like suspension, exhaust, or pulling a tranny is probably okay to push into the morning even though there'll likely be more cursing than progress at that point haha but this is definitely the last time I do precision work on an engine that late. Lesson learned....

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