[John Galt]

08 xB. 142,500 miles. "Loaned" it to son/DIL for 3 years (son is NOT mechanically savvy). Suddenly developed rough-running - comes n goes - oil consumption up - "misfire" and O2 sensor codes. We retrieved the car, as their local stop-and-rob Toyota dealer quoted "engine-replacement - $10,000" without investigating anything. Thinking it was coil-pack - I asked son to swap 1-2 - now misfire on 1 AND 2 (he did that before we were able to pick it up). Got it home, and compression test found #1 with NO compression at all. Hmmmm, must be stuck valve? Removed rocker cover to check. Intake cam - inner flange at main bearing boss - doesn't look like the exhaust cam. The flange - i.e., a machined part of the cam casting - BROKE OFF from it's position on the cam and wedged-open one of the intake valves in #1 (looks like a big thick "washer" flopping around on the cam). My suspicion is that it was a defective casting. There is nothing preventing "endplay" now, except the timing chain tracking with the tensioner and the exhaust cam sprocket (of course we're not driving it). Anyone ever replace cam(s) without removing engine? I'm up for trying it if I don't have to horse the engine out of there....

 

[John Galt]

First off, Welcome to the club! This is over my head but I will say: Yes it's easy to replace the cams- just do it with the stock ones from a Junkyard- because everything is right on top- 1.8 Tony or Superbee44 ( knowledgeable club members) probably have done this a few times.. They may chime in. And yes $10 grand for a motor is ridiculous, you can get them for $900 to $1,200 low miles at a JDM motor sales shop.... Others should chime in.. Again Welcome.

Thanks for the come-back - being a NOOB, that encouragement is helpful. Late yesterday, wife found a pair of cams online for $80 (she's real good at interweb stuff), and I found a pretty good how-to video, so I might try it (I'm 70 years old with gimpy knees, so that sitting on the ground and reaching past the wheel to get to crank and chain might cause me to farm it out). Wife's really disgusted with the kids - car looked brand new when we "loaned" it to them - now dents and scratches and nasty innards, and not very attentive maintenance...but she wants to drive it again.

 

[John Galt]

Yeah - I get it. Bought my first car (1962 Chevy II 4-door) for $225 in 1968, and I did / paid for everything except insurance - including re-ring and new crank/rod bearings. Did all my own wrenching ever since (some of it I should have left to people who know what they're doing), but now am letting others "do" instead (knees ain't lettin' me down on the floor too easily). Waiting on some more parts now. Got the cams out (and the ones from evil-bay have arrived), and now waiting on intake cam bearing. Looking from a foot away found driven-end cap really got HOT - hot enough to melt the side of the insert and the cap - friction from that flange on the cam...looking from 8" away with the close-up glasses found that the bearing insert in that cap was canted about 0.060", and covered about a quarter of the oil inlet as it comes through the cap, i.e., the oil wasn't being directed properly, and I'm guessing it was insufficient for the outer edge of the bearing surface (towards the non-driven end) of the only actual "bearing insert" between both cams. Both halves of the insert had pretty pronounced grooves inside. Can't guess if this was an improperly fitting / installed insert, or an improperly machined bearing cap, or... We'd bought it in '08 with 12,000 miles on it, and racked up another >110,000 trouble-free miles - always changed oil at 5K with 5W20 synthetic, and used WIX filters; can't get a straight answer out of the kid - who put about another 20K on it in three years. Oil change? (Not likely.) I'm hoping it all works - wife really likes driving it. To me, it's like driving a damn go-kart...if you happen to sneeze, you're suddenly northbound in the southbound lanes of a 6-lane interstate, and a 1/32" press on the gas gets you 3g's of acceleration. I'll stick to my '52 Willys Jeep or my '96 F350 crew-cab dually.

Well I had my Dad's 1979 Impala station wagon and I drove it into the ground not caring about it because my Dad owned it and paid for all the repairs back in 83. Kids seem to learn to take care of things when they have to pay for it.. 😆 Let us know how it comes out!

 

[John Galt]

I see a broken Toyota cam shaft like that two or three times a year. Dangerously high engine rpm's create higher oil pressures. Higher oil pressures cause the cam to "walk" towards the thrust surface resulting in friction & heat which wears away the surface material. This material then washes down into the oil pan it then gets pumped into the oil filter and because the oil filter is under a high amount of pressure, it's internal valve opens and the filter element gets bypassed resulting in the contaminated oil getting pumped up throughout the engine bearings.

Hopefully you've cleaned the timing chain properly and marked all appropriate chain links to make timing the engine trouble-free.

Tony - thanks for the how-stuff-gets-damaged assessment. While waiting on the used cams and bearing-caps, I got everything disassembled and inspected. Caps and bosses - except for the tore-up one - looked pretty good for 142K, at least I thought so. Chain wasn't side-to-side sloppy at all. Followers didn't appear to be marked up - just some discoloration - even the one that had that broken-off flange wedging the valve open (#1-intake, closest to the cam-phaser). I only used the replacement intake cam, and did a "fingernail" scratch test on the bearing journals on both it and the original exhaust cam - used narrow strip of 600-grit emery paper on each - counting see-saw motions 3 times around each one until they were smooth. Used an entire can of brake cleaner on/in each one to clean them, and another couple of cans on the head and chain. In the well next to #1 follower, I used a magnet to retrieve probably 1/4 tsp of iron bits. Got cams in, tensioner snapped in, oil changed (made sure chain got a good dose too), and then cranked it for 15-20 seconds to make sure oil was getting to the head OK. Cam cover back on - coils - and then cranked for a run. Happy to report the initial "stumbles" quickly disappeared and it ran smooth within a few seconds.

I'm just guessing... I found a Pennzoil filter on it - I know the kid would in no way have changed it himself, but I don't know what stop-and-rob quick-lube place uses those products. I noted that the oil that I was blowing out of the wells in the head, with the brake-cleaner, sorta' reminded me of the juice from prime-rib - little globules of fat swimming around - the brake-cleaner didn't really "dissolve" it as much as it just loosened it up and floated it away. The drained oil was also NOT 0 or 5W - anything - it was THICK, and could have very well been NOT synthetic. I'm guessing that was more likely the cause of this problem - too-thick oil, run too long, and maybe made from dead dinosaur skin instead of re-constituted "gas." Will change the oil after a few hundred miles, and replace with 5W-something and a WIX filter. I saved the old filter - will see if Hobo-Freight has a filter-cutter - would like to see what's in it.

Thanks again!

 

[John Galt]

No need for an oil filter cutter.....you can stab the oil filter near the crimp ring.... The cramp ring of the oil filter is the portion of the oil filter closest to the gasket.......once you stab it, use some snippers to snip around the diameter of the oil filter shell, and then remove the shell.

Remove the filter element and wash it out in a container of gasoline and find all your metal debris.

I like your thinking - "use what you have." I've become a bit lazy in my old age....

 

[John Galt]

So...all back together - a can of Berrymans in a fresh tank of gas - about 300 miles on it so far. I DID cut the filter open and washed it in gas - got close to half a teaspoon of filings on the magnet when I fished it out of the gas. What I "think" happened could be a combination of several things: 1 - the Midas stop-and-rob "special" oil change that I had done (was in a hurry - shoulda' done it myself) either didn't use synthetic 5W-XX, or used cheap dinosaur oil 2 - young son never had it changed in nearly 25,000 miles (Penzoil filter - same as Midas - not WalMart) 3 - oil level got low 4 - young son rev'd it pretty good when low on oil. (Note: this car, with >120K on the clock when we "loaned" it to the kid, would go 2500-3000 miles without needing to add oil.) Regardless, I believe that lack of lube at this bearing caused things to get plenty hot. "Hot" flange - relative to temp of rest of cam - caused expansion of flange without equal expansion of cam - and the flange separated from cam - flange got wedged between cam and #1 intake follower, holding valve open. Kid takes it to Toyota dealer - "needs new engine - $10,000;" they "said" they ran scan-tool on it (which showed "misfire on 1 and 2). 1st pic is the intake cam main bearing cap with both upper and lower inserts in the pic. HOT_HOT_HOT. 2nd pic is the cam - where the flange broke off. 3rd pic is the flange - plenty scored. 4th is the "outboard" flange that runs against the other side of the bearing cap - no signs of heat, but not knowing the tolerances, I can't guess how much wear there really is. All in all, I guess my recommendations are: #1 - change the freakin' oil at 5-7k. #2 - ALWAYS use 0W or 5W SYNTHETIC oil. #3 - don't "drive-it-like-ya'-stole-it. #4 - check the oil once a week (that was my job at home - as a teenager - in the mid/late 60's) - make it a habit.