80 Series 1FZ-FE Valve Repair without removing Head (1 Viewer)

[RECRUISER]

So this forum has helped me out so many times in the past, out of respect for those in this forum and to the seekers of solutions that visit this site in the future, I am documenting this repair.
My problem started with my 1997 40th Anniversary Land Cruiser with a Miss in cylinder #4. This problem went continuous 3 weeks ago and my vehicle was un-drivable because of the extreme miss.
Snap On scanner confirmed the miss was IN CYLINDER 4. Watching live engine data, the numbers of misses in cylinder #4 was adding up like 4 per second. I did a compression check next and like I was fearing, it had ZERO COMPRESSION.

So I pulled off the throttle body and pulled the Valve Cover only to discover that one of the intake valves to cylinder 4 was stuck down, and wasn't popping up fully to seat. So that explained my massive miss and zero compression!

I used a bore scope and saw that there was no damage to the cylinder head or the valve. So there was no damage.

Using the FSM, I removed the intake CAM and dropped the timing chain and gear back, which fully exposed all 12 intake valves. (heck I figured I'd be taking the head off anyway next so what did I have to lose?) I wanted to remove the lifter so I could inspect the valve keepers and retaining ring and see if a spring was broken etc... Everything looked fine.

I was getting ready to order head gasket etc. and pull the head, when I decided to try and push down on the stuck valve. At first I couldn't move it at all, but then I used a long wrench and hooked it under my EGR assembly, and used a socket extension placed on the stuck valve #4 and used the wrench as a lever pressing down on the socket extension. This allowed me to put considerable down force directly on the stuck valve and to my amazement, it moved! Downward at first and then when I let off I could tell that it had moved higher!
Several more times up and down and it was moving properly and seating completely and moving like the other valves when I pressed on them in like fashion. I Did a leak down test by putting compressed air in the cylinder and it passed! So the valve was seating completely now.

I put a liberal amount of Schaffer Penetrol down each intake valve and let it sit for a day with those valve stems and lifters soaking.

Yesterday I re-assembled and it started right up and ran like a champ!!!!

So this thread was created to give hope that you may be able to avoid pulling the head if you have a stuck valve. This Cruiser had sat for over a year, and if they set for long periods of time valves can give trouble if they sit with those valves in the pressed down position. with varnish setting up on them like concrete.
Hope this helps someone out there in the future!

 

[inkpot]

So, why was it stuck? Bent, burnt, debris/interference, bucket damage, etc?? Something made it stay open. Been there done that. Had an alignment dowel from the upper intake manifold unknowingly fall down the lower runner during disassembly and wedge in #4 intake valve at the rear of the chamber. Out of site! Cylinder had ZERO compression. We went nuts trying to figure that one out, but we got it.

 

[RECRUISER]

I called the previous owner and found out that the Land Cruiser had not run for MORE THAN A year before I bought it last month. My theory is that the cam had been pressing down on cylinder #4 for that whole year. During that time that valve stem was exposed to whatever condensation was present in the cylinder due to changing temperatures and sweating etc for that whole year. During that time exposing the valve stem to rust build up.
But anyway when I started putting significant down force on that intake valve it took a while before it moved as it was really frozen. Then when it started moving it was just a couple of strong down force pushes that it came all the way up and seated itself. It was almost acting as if it was a bent valve so I feel fortunate that I kept trying and was able to place enough downforce on it to free it up.
Like I said I'm feeling fortunate and I hope this helps someone down the road avoid a very time-consuming head removal.

 

[mehbohdi]

It's' the simple things that make one happy once in awhile..... I wish all things were that easy

 

[Mighty690]

Smart.

 

[Rifleman]

So, why was it stuck? Bent, burnt, debris/interference, bucket damage, etc?? Something made it stay open. Been there done that. Had an alignment dowel from the upper intake manifold unknowingly fall down the lower runner during disassembly and wedge in #4 intake valve at the rear of the chamber. Out of site! Cylinder had ZERO compression. We went nuts trying to figure that one out, but we got it.

I had one of the guys in the shop remove a customers carb to rebuild it, to keep crap from getting down inside the intake manifold he stuck some shop paper towels down inside the intake runners. He finished up overhauling the carb, reinstalled it, then tried to start it. Problem was, it would just not keep running. So he calls me over to help him figure out why it won't stay running. I ask him to crank it over again, the motor cranks over slowly, it wants to start, but just won't stay running. So I'm walking around trying to figure this out, because it was running when the customer brought it in. I just happen to walk around the back of the car, and noticed a bunch of debris that had been blown out of the tail pipe. I pick it up, start looking at it, it kind of looks like shreaded pieces of paper. So i ask him to come take a look at this stuff coming out of the tail pipe. Man, if you could have seen the look on his face, as soon as he saw it, he knew what he had done. That's when he had to tell me, oh, by the way boss, i think i may of left a bunch of paper towels in the intake manifold!!!! Needless to say that little mistake ended up costing us a valve job (it bent more then one valve) on that customers car at our expense. I was pissed when it happened, but We laughed about later, it's just one of those stupid mistakes that can happen to the best of shops, live and learn.

 

[inkpot]

I called the previous owner and found out that the Land Cruiser had not run for MORE THAN A year before I bought it last month. My theory is that the cam had been pressing down on cylinder #4 for that whole year. During that time that valve stem was exposed to whatever condensation was present in the cylinder due to changing temperatures and sweating etc for that whole year. During that time exposing the valve stem to rust build up.
But anyway when I started putting significant down force on that intake valve it took a while before it moved as it was really frozen. Then when it started moving it was just a couple of strong down force pushes that it came all the way up and seated itself. It was almost acting as if it was a bent valve so I feel fortunate that I kept trying and was able to place enough downforce on it to free it up.
Like I said I'm feeling fortunate and I hope this helps someone down the road avoid a very time-consuming head removal.

Sounds like you lucked out, for sure. I'm surprised you didn't have to do that to the second valve since they are twins.