CoreyZ/28

iTrader: (2)

My dad has an '05 Envoy with a 5.3 in it. He is in the process of getting the cam bearings changed out. When I pulled my cam in my car, I spun the cam a few times and the lifters stayed up, no problem. When I spin his cam over, the lifters dont seem to stay up so I decided to use the 5/16" dowel rod trick. Well as I spin the cam to get the lifters up to the point where the dowel rod can slide in and hold them up, it seems to never get high enough to get under them. The only way I could get the wooden rod past the lifters was to tap it with a hammer. It seemed as if the rod slid beside the lifter and wedged it in place. This didnt seem right and I havent pulled the cam yet. Just wanted some1 to chime in as to whether I'm missing something or if what I'm doing is somewhat correct.

wildcamaro

iTrader: (15)

I'd just pull the heads if you think something went wrong it would be easier to just pull lifters...head gaskets and head bolts would be under $100 in parts

Paul Bell

iTrader: (9)

I'm sure there's a better way and somebodies gonna chime in with it but don't hammer in them dowels. Doing so may leave wood splinters and stuff where you don't want them-in the engine.

96capricemgr

iTrader: (1)

I thought pen magnets was the ticket for holding up falling lifters?

86lxnotch

iTrader: (3)

i just did this today on my 6.0, i got the 5/16'' dowels and the driver side went in but the pass side wouldnt. i ended up using a 1/8'' piece of alum tig filler and it worked perfect. rotated the cam on the way out a few times and it was fine

S10xGN

iTrader: (11)

Same here (mine went in, but only from the rear), next time I'll use the half-rounded brake tubing trick instead of wood. Hmmm, or find a way to mill the wood dowels flat on one side. It could be the lifters, too. I've seen lifter bodies that are solid from top to bottom and bodies that are slightly sectioned out in the middle, which would allow more clearance for the dowel to slide past.

35thPewterZ

iTrader: (2)

used this method a couple times... pretty easy if you have enough magnets laying around

86lxnotch

iTrader: (3)

next time i do one ill prolly just use 1/4'' dowel

-Joseph-

iTrader: (12)

I've used the 5/16" wooden dowel trick a few times on the engine dyno, specifically with the AFM/DOD lifters on the L99 6.2L. They were very snug fitting at first, I ended up using some cam lube and twisting the drivers side rod by turning it clockwise as it was installed, and the passenger side rod by turning it counter clockwise as it was installed. Using that method, the lifters were pushed up into the lifter trays as the dowel was rotating.

Once the dowels were used a few times, they worked much better. I kept them around for 30-40 something camshaft swaps on both the L99 and LS3 and will likely do the same next time I do a bunch of camshaft testing.

Things I would be careful with:
Do not grind the wood away into the engine, lol
Do not break the rod off inside the engine!
Do not light the wood on fire inside the engine.

I've heard of ppl using 1/4" dowel rods, but I'm not sure they would provide enough friction/bind to hold the lifters up. Sure they might hold them from falling, but ideally you want the lifter high enough to clear the camshaft lobes and journals.

86lxnotch

iTrader: (3)

Well I used 1/8" Tig rod on the pass side and just rotate the cane gently as I brought it out an it worked better than the wooden dowel imo

01ssreda4

iTrader: (96)

The rods don't go under the lifter, they go to the side of it.

SSZ

What would the length of these rods be to get all the way into the engine? Would some 5/16 threaded rod be ok or even some fuel line?

-Joseph-

iTrader: (12)

Approximately 20 inches each side and that would leave 2-3 inches for removal. The nice thing about the wooden dowels is they have some give to them whereas steel would not.

S10xGN

iTrader: (11)

I sure wouldn't use threaded rod, but fuel line (like brake line) has some give and should work OK.

im-not-guilty

iTrader: (4)

cam bearings man ??????
how come ??????????
i have worked at the dealer since the ls motors1st cam out and have yet to change a set of cam bearings?????????

SteveDoten@ARH

I pulled the heads on a 5.3 Envoy last week; it was the Denali version with the DOD lifters(4 on each side), 1,4,6,7 IIRC

GM has a TSB on the DOD lifters failing(the truck had dead cyl. on #6)

$45x8 was pricey compared to the $60(set of 8) for the conventional LS lifter

135,000 miles; the new lifter fixed the problem, cyl. 6 is back in the game

Truck was a 2006, not sure if the Denali version was the only one to get the DOD?

how did you find the cam bearings worn?

SSZ

I just did a cam swap yesterday and the 5/16 wood dowels worked great. i found the drivers side was tighter than the passenger side. 20 inches was on the money too. Glad this topic was up when i was ready to do the swap. Thanks for the help.

CoreyZ/28

iTrader: (2)

The service manager at my local GM dealership was the 1 that suggested the cam bearings so evidently it happens. He also told me that when it comes to something as involved as cam bearings, they outsource the work or just replace the engine. This may be why you have never changed a set. The rods and mains were fine but the cam bearings were definitely hurt tho. Should be starting it sometime this week. The lifters in this engine were solid from top to bottom with no reliefs for the dowel rods to fit in so I decided to turn the engine upside down so gravity could hold the lifters in place.

98SSHARDTOP

The dowels wedge on the sides of lifters, that's the intent. They don't hold the lifters from underneath. Pass side always tighter, shave 1 tip of the dowel rods to use on that side, once it starts, it'll go rest of way easy.

M33P

Holy thread revival batman!