Lobes & lifters worn- how would you approach repair?

  • I`m procrastinating. Something bad happened to the GTs new engine. I've moved it to rv pad. Rear is on stands, hood is loose...I could've removed and used picker to lift front on way-high stands, but I took a nap instead. This all didn't JUST happen. I've been to machine shop, I've talked to parts supplier, I've examined and measured parts, I've stood there and looked at GT for multiple 10 minute stints...and then took naps. Today I got off work early with intentions of working on Opel- found it right where I left it - but it was cold outside and the house was all mine...so, yeah, I napped. When I woke up there was some daylight left, so I visited opelgt.com, then craigslist, then here. Hmmm, good opportunity for procrastinating with a long post, composed with thumbs on a kindle! Probably won't get read for awhile, maybe not even see a reply (always ensured by not posing a question up front). But hey, this is my impasse - exclusively here at classicopels for anyone to join in on.


    The last 30 miles on my 800 mile old rebuild I began wondering "Has that rocker noise always been so noticeable?" - so I pulled valve cover and ran it, finding #2 hydraulic ex over a turn loose off preload! Must've backed off- easy fix. Noise was much better, but still seemed overall loud... 5 miles later I find it's loose again (but the nut hasn't moved). This sucks.


    #2 ex lifter wouldn't pull out top, so I pulled the head to disassemble. #1 ex lifter was missing its crimped-on assembly retainer and the face was worn concave (as were 2 3 4 ex). #2 ex was worn worst and extracted out from inside. All exhaust lobes had severe corresponding wear-down. #1 ex lifter crimp ring is MIA and probably gobbled low and tossed throughout. Lower of front cam brng is just starting to take shape of cam oil groove. All INTAKE lifters and lobes are 800 miles PERFECT.


    I need to finish a shopping list...so far I've listed head parts, but that could grow depending on how far I need to chase this down. I don't desire starting all over again with block disassembly, but I'm curious if rod and main bearings are polish wearing. Machine shop advises drop, measure and clean everything; Parts Supplier advises just clean and repair head parts, then put neodymium magnets at filter and drain plug to capture remnant debris.


    I'll only hate you ;) for siding with machine shops advice...I know it's safest answer. Maybe there's some shareable experience to help justify needing redo of top only, or perhaps workaround tips to check condition of rest of block in car. Any insights?


    -Dan

  • So... 800 miles after a rebuild, all 4 exhaust lifters are damaged and the exhaust cam lobes are worn. But the intakes are fine. It sounds like the exhausts were set too tight. zero lash plus 3/4 to 1 turn (after they are pumped up) is the setting. If it was just one lifter, I'd say it was defective or the oil galley was blocked and starved the lifter. But all 4?


    One other thought. Was it a new or used cam?

  • I agree, those are good ideas to look in to. Maybe spring bind, too. Lifters and cam were new.


    Incedently, my prior engine rebuild held the surprise of a poorly aligned front cam bearing and thus very restricted head passage oil flow. Failure manifested at front cam bearing, and as chain pulled cam down into wearing bearing, cam oil groove became occupied by the bearing and flow was further restricted. Cam fulcrumed at bearings 2-3 and wore away top half of rear bearing. It made it 2000 miles before losing oil pressure and splattering particulate on to rear of cam sprocket.

  • Hmm, appears I shared confusingly. Sorry. Oil passage blockage and what happened was failure of last engine. I started all over. Exhaust lifters/lobes is current failure of a separate engine build- I reused the timing chain, valves and water pump, but otherwise no parts sharing. This head received hardened seats, new guides & bearings, and threaded galley plugs. Yep, only damage to exhaust lobes and lifters.


    There's no good shortcuts in sight for me... yesterday I drained oil, pulled alternator and distributor, unhooked wiring and fuel lines, modified a pair of tall stands for front of car, and got picker positioned and chained to front suspension for lifting. Engine is coming out soon!

  • Failure cause determined. Apparently vendor had a batch of BAD lifters a cpl years ago. Turns out I had bought 4 of those to troubleshoot what I suspected was a tuning problem in first engine build...but never got opportunity to install them- and so THOSE 4 unused lifters found a place on ex lobes of my second engine build (THIS engine with failed ex lobes and lifters).


    Ended up doing a full teardown, inspection and reassemble with a new cam, lifters, bearings, gaskets and seals. Vendor comped $180 retail of the bearings off the parts order.


    The gt is back on the road and running well - so far- with about a hundred new miles behind it...and I'm hoping it holds together this time!

  • Failure cause determined. Apparently vendor had a batch of BAD lifters a cpl years ago.

    Can you take a picture of them.. ? I know a few in europe and china were in the process of reproducing the lifters.


    Most the motors I built I used these new lifters and had no problems.. that I know of. Curious if the bad batch came from the same place. I have a feeling they didn't but want to be sure.

  • I wanted to add these photos for information of some of the lifter failures. 1492 is a factory hyd. lifter 6506 and 6500 is a bottom photo of a failed replacement lifter , the last photo is the rocker arm ball end.

    What I found was the rocker ball end did not fit into the the seat at lifter and only caught the edge which damaged the rocker arm. This also caused the lifter to not spin or rotate (this will wear down a cam lobe). You can also note pitting on the lifter base but that lifter also tried to spin but with rocker hanging up in the cup edge it damaged the rockers and results was worn cam, lifters and all rocker arms.

    This damage was found on 3 different engines here in GA and built by other people and most only had less that 500 to 1000 miles on engine.

    I took one of these engine apart and took photos so we will have this info. here and it may help someone.

    Some of the hyd. lifters out there are giving problems and it's getting harder to find hyd. lifters so you can get your factory lifters rebuilt and base resurfaced at this time and should work for you.

  • When I bought my wagon from a guy in NJ, he told me "the motor was rebuilt by the most reputable shop in NJ."


    One day, I was driving it and all of a sudden the oil pressure dropped. I shut it down. After a couple of minutes, It started and ran normal.


    When I got it home I pulled the rockers and noticed 2 of the lifters had holes in the center where the rocker rides. The ball on the rocker was worn and had a small bump from the hole causing the rocker to shift and oil pressure to drop. Evidently, they substituted a lifter from an OHV motor which uses that hole to lube the rocker for the Opel one. The lifter dimensions were the same with the only difference being the hole in the center.


    There is a GM lifter somewhere out there that we may be able use by swapping out the center piece.

  • Can you take a picture of them.. ? I know a few in europe and china were in the process of reproducing the lifters.


    Most the motors I built I used these new lifters and had no problems.. that I know of. Curious if the bad batch came from the same place. I have a feeling they didn't but want to be sure.

    C- Sorry for belated reply (I'd began thinking this site was just for "Dan chats with Gary" LOL)...he's great and all, but he tunes in at the other site too - and I've neglected returning here for quite a while.


    Also sorry, I think no pics remain of that era. I had been solely logging my opel pics/activity in a big provider platform that wouldn't disappear...Google+. Alas, gone.


    Here's what I can recall and share that should help you: hyd lifter retainer caps were black and stamped with 3 letters, came pkgd unmarked ea in a plastic bag stuffed into what what resembled a clear 35mm film canister, sourced probably late-ish 2015. Hope this much helps.