What reasoning do you have behind that? All I did was unbolt it, change cams, and bolt it back up. The seal appeared to be in fine condition.

I guess I might as well, while I am there. I will get a new seal when I get a new pump.

Any comparisons/recommendations on pumps between:

ls6 stock pump $95
melling "high volume" pump $130
gm performance "high volume" pump $70

 

Well, I gues my decision was made for me, since sdpc was out of everything except the ls6 pump. I went ahead and got one on the way to me as well as the new cam retaining plate/seal. Guess I'll be doing the job again at the end of this week. At least I can start the truck and bring it inside so I dont have to do the work in the 22 degree wind outside.

 

I don't know what to think about this. Considering that you had good oil pessure before and now you have fairly good oil pressure cold but poor oil pressure, that tells me that it has something to do with viscosity. The only places that you could be leaking would be the front retainer plate with integral seal (unlikely as you have said) the pump itself is not working well (I think that this is unlikely too) or the oil pickup tube O ring is not sealing well (still a possibility but I think that you understand this issue better than many who have problems).

Are you using the correct oil pickup O ring for the truck application? The pumps are the same, but the truck O ring is thicker than on the car (I believe). As I recall, one is black and the other is blue.

Steve

 

That's what I thought too when I swapped mine, but when I got the new one, there is a noticable difference between the two.

 

If that thing causes this many problems then it seems like a design flaw with this series engine that should have been/needs to be addressed. Why didn't they just use a flanged pickup and a gasket, like most other setups? There would never be any question, because if you look there and see a gasket sticking out a mm or 2 at the flange, you *know* you are good to go. None of this second guessing bullshit.

I can't stand design flaws.


Prior to yesterday the pump had never (to my knowledge, that I could tell) been disturbed. It had a fat green ring on the pickup. I simply wiped it off, looked it over, coated it in vaseline to hold it in place and help it slide on the tube, and put it back up into the (now clean) oil pump. SO, it is the stock oring that GM installed in late 01.

I bought an ls6 pump from sdpc which is supposed to come with a new oring as well as a new cam retainer plate/seal. We'll see at the end of the week.

Based on this experience, I now feel that the people who swap LS1 setups into rx7s and claim it increases reliability and ease of repair are freaking insane. I'm going to start telling these people that a simple tank of bad gas caused me to:

bend 3 pushrods severely
crack lifter guide plates
break/grind down a lifter
grind down a cam lobe
have to pull the heads to replace the lifters
have to change the cam
have to pull the oilpump and oilpan and reinstall
have to pull/replace the oilpump again

Cost without labor is up around a grand right now...

 

Okay, I am super f*(&ing pissed off right now. My new ls6 oil pump and cam retaining plate came in today. Installed the cam plate, the old one looked fine.

I poured some oil into the pump and turned it by hand to coat the internals before installing it. I was attentive to the green oil pickup tube during install. Button it all back up (except for steering and front axle stuff) and fire it up to check pressure. I see about 30 cold, and let it warm up all the way and it drops to around 10.

So, I figure, maybe the sender is bad. I realize it will be impossible to get it out without breaking it unless I remove the intake, so I do. I pull the sender and install a mechanical gauge temporarily, throw the intake back on and fire it up (still warm). I see 10psi at idle and 20 when revving.

WHAT THE HELL!

I am about to pull my friggen hair out. This is some bullshit. That turbo rotary swap is looking better and better every day.

 

did you ever change that 5$ o-ring for a new one. I had the same problem 2 weeks ago it lt LOOKED fine, but a new one proved too fit really tight when installed,and my problem was solved .

 

Well, that's something else I am pissed about. A new oring was supposedly included with the pump, but then it shows up and there is no o-ring. I am going to check around the 2 local dealerships today to see if they happen to have one on hand.

 

For one, how does a bad tank of gas cause all of this? Second, if you lost a lifter and cam lobe it is quite possible that all of that debris has wiped out the bearings. If that is the case, no oil pump or o-ring will fix your o.p.

 

red o-ring did not change anything, pressure is still 10-20.

The bad tank of gas would not let the truck start, and when it did, it ran poorly and backfired through the intake a few times. Later I sucked out the remaining gas and replaced it, the fuel filter, and injectors, and it fired up and ran with a lot of valvetrain noise. Then I found the bent pushrods. The truck did not leave the driveway or rev over 2500rpm during all of this.

 

At this point the bearings are probably wiped. I have seen it many times after the lifter fiasco. Small base circle cam + worn lifter trays = nastiness.

I am sorry for the problems you've experienced. I hate to hear about these horror stories.

I hope this is not the case for you but you are running out of places to check. You will have to pull a main cap to inspect the bearings at this point.

If you need any advice or want to run through the whole thing again give me a call at the shop and we can brainstorm it.

Thanks,
Shane

 

here is something really odd. I put the stock sender back in it's hole behind the intake, and moved my mechanical gauge down to the plug on the drivers side lower corner of the block, behind the PS pump. Fired it up and at idle see about 20 on the stock gauge and 35-40 on the mechanical gauge. I rev it up around 2300 and see 50 on the mechanical gauge while the stock gauge stays at 20-25.

Note that I already pulled a rod cap and that bearing looked fine, as did the front cam bearing when I had the cam out.

 

Looks like I am just going to pull it out and apart to see what else I can find. I'm at a loss at this point.

 

As a follow up, I pulled the engine and found the problem. Cam bearing was bad, chewed into the journal on the new cam. I have no idea what caused this. The old cam had no journal wear at all, slid out freely, and the new one went in easily too. I was pretty careful installing it and am pretty sure I did not nick the bearings, but I guess anything is possible.

IT doesnt look like it spun inside the block, but being near the middle its kinda hard to tell at this point (heads and rotating assembly still installed).

I'm probably gonna check some main and rod bearings and decide whether to try and repair this one or just go with some other replacement engine. The other 4 cam bearings look fine.

 

Good thing you found the problem! That took alot of work! That sucks you're gonna need more new parts! Goodluck man!

 

Later found that all the main bearings and the crank journals have some wear on them as well so I am likely going to just find a used or rebuilt longblock and drop in as a replacement. I can find used engines for a grand or 1500, and even if I reused these rings I'd have a good $5-600 bucks in replacement bearings, crank, fasteners and misc. costs.

 

if u need a replacement engine, i have a friend who is selling an LS1 engine.

 

How much? Specs/condition? I am really looking for something local/regional so I can avoid shipping and possibly getting shafted on a deal (versus inspection in person). I've got a couple leads at this time.

 

RotaryResurrection,
How long had you had this truck before you had the lifter problem and then discovered the oil pressure problem? I'm wondering if there were any early warning signs and the conditions under which the problem occurred with the lifter.

Steve

 

I bought the truck about 18 months ago with 67k, and it now has 88k. I ran castrol 5-30 synth in it since I obtained it, and compression was excellent across the board. Other than the usual "GM sewing machine" click clack at idle it never had any issues.

Back in the fall, one day the truck wouldnt start with the remote starter, which had never happened. After applying lots of throttle and cranking for a long time, it fired up but ran poorly with vibration, like on 5 cylinders, with a ton of smoke from the exhaust. As I held the throttle and it warmed up, it ran progressively better and I could reduce throttle, and when it was at operating temp it idled perfectly and drove normally with no smoke. I figured I had a bad tank of gas. Given that GM didnt see fit to give us a drain plug, I figured I'd just try to run all the gas out.

The next 2 days I repeated this process without incident. The first cold start was hell, but after it was hot it would run perfectly even on restarts. The 3rd day I had run most of the gas out, but the truck wouldnt start at all for like 10 minutes. I sprayed some starter fluid behind the throtle plate and tried to start it. After lots of throttle and cranking, and a bit of backfiring, it fired up like an old tractor running on about 2 cylinders. Eventually it started smoothing out as it had for the previous few days. But it never did completely, and I had a new valvetrain racket.

I found 3 bend pushrods on the front 3 passenger intake valves. Replaced all the pushrods. I also sucked out the remaining fuel, put in fresh, blew out the hoses, new fuel filter, zero mile injectors with rails. Then it ran pretty much normally. BUt after a couple hundred miles I had a light tapping in the valvetrain. The more time went on the louder it got.

Couple weeks ago I took it off the road to do more repairs. I did all the lifters, headgaskets, etc. Found the bad lifter that ground into the cam, so I replaced the cam with an aftermarket one. Which then necessitated new pushrods.

Then I fired it back up and it had no valvetrain noise for a few moments as it warmed up. OIl pressure was fine. I pull out of my driveway and get a couple streets down and see the oil pressure is low. By the time I get back home, the pressure light is on and I have to throttle it at stop signs to keep pressure above zero.

From then on it was weak on pressure, despite oil changes, oil pickup orings oil pumps, etc. So I guess the cam bearing spun within the first few minutes of running.

I am really sure that I did not gouge a bearing during cam install, I was very careful and the cam was well lubed. It went right in and spun like butter.

So, that is the story of how a simple tank of questionable gas eventually brought down my mighty gen III iron block american v8 despite my best efforts at maintenance and repair.

Meanwhile I am hauling engines and actually had to towdolly a broken down family member's car with my (generally reputed as sensitive, unreliable, and torqueless) turbo rotary powered rx-7.

The kicker will be when I drive this weekend to retrieve the replacement piston engine for my truck, and tow it home with my turbo rotary. Yes, there will be some **** talking on the internet once those pictures are posted.