sdoolin

Finally got around to building an engine for my 87 4Runner. Called the guys at LCE and gave them a pretty big bucket full of money. I had the $$ to spend, had a spare long block, have no desire for a "contemporary" SUV, and have been wanting to do this build for quite a few years.

So....

.040 oversized Hyperutectic (sp?)pistons, 1mm oversized intake and ex valves, new valve springs, new rocker arms/shafts with high flow oil passages, "pro-torque" cam, competition port/polish on the cylinder head, balanced rotating assembly, oversized throttle body, cold air intake, header and complete free flow exhaust, competition oil pump, billet aluminum "power pulley", super cool red plug wires with wire loom (bling), dual row timing chain conversion with steel backed guides, new timing cover, new water pump, all gaskets/seals/etc, along with new head bolts, ex studs, intake studs and I'm sure some other crap I'm forgetting.

My goal was to stay within the operating limits of the stock EFI and pump gas. It is all I can do not to order dual Webers, it still might happen.

A few pics are in order...

Engine coming out...


Short block assembled by local shop...




Long block with dual row timing chain assembled in my shop...






Cylinder head...




Will post a few more pics later. Engine is in and is/was running fine. I got about 45 miles into a pretty normal break-in sequence with the engine feeling quite strong above 3400 rpm (several heat cycles - drive/rest, drive/rest, etc), was idling just fine with no surging (EGR removed, TPS verified) but I have lost compression on #4 cylinder.

Dang it!

Engine turns freely by hand, cam lobe and rockers and valves on #4 appear just fine from the "top" side with no sticking or bending, (assembly lube used as appropriate and all torque specs followed) have not removed head yet. I'm hoping for a blown head gasket as opposed to a holed/broken piston or rings that have somehow vanished.

Thoughts?

sdoolin

One more pic, this should be in the LCE catalog...

yodafan93

ew. fram. other than that looks good!

sdoolin

Ya, Fram was on the shelf, it is for break in only.

wyoming9

iTrader: (1)

Just curious why you would spend so much money on a 22REC engine???

What was your goal in the long run??

That seems now to be having issues all ready.

It does look pretty !!

sdoolin

So, and update, and I am stumped. Like mentioned I lost compression on number 4. The numbers were:

#1 = 150 PSI
#2 = 150 PSI
#3 = 130 PSI
#4 = 30 PSI

I checked these all several times, with the engine warm. Friend of mine called the next day and asked if my compression tester could double as a leak down tester, and I discovered it could. With all spark plugs removed, applying shop air to #4 with valves closed actually turned the crank and either the intake or exhaust valve would open. So - seemingly no hole in the piston.

Installed spark plugs in #1, #2, and #3 and re-did. Shop air (at 110 PSI) did not turn the crank, and air could be felt escaping at the cam chain cavity (front of head).

So I was still thinking head gasket. But - (but) - removing the cylinder head reveals what looks to me like a perfectly good head gasket. Appears sealed well to both head and block.

I am stumped.

The coolant came out looking brand new, the oil came out looking a little too "shiny" for me. No marks on tops of pistons, all spark plugs have very similar burn pattern, and while the combustion chamber and top of piston in #4 are very similar in terms of color/burn pattern to the rest, the intake valve on #4 is black whereas on the rest not so much.

Maybe a rocker arm stuck, or valve guide too tight?

Like I said, I am stumped...

Since we all like pics, here is how things looked right before my last break in run, engine with about 40 miles on the rebuild (truck with 257k)...


Any helpful thoughts appreciated.

yodafan93

are youre head and block true? take out a straight edge and some feeler gauges and see what you find. maybe its un even? maybe there was crud in the headbolt holes and you got an inaccurate reading when you torqued them down?

sdoolin

I am going to re-check those, but when it when together it was done practically in a medical clean room (I am a little anal about cleanliness in my shop). Head bolts are new, were oiled and definitely properly torqued. Short block was surfaced and head was surfaced.

It is certainly a mystery....

Kiroshu

-Check Valve clearance(lash)..?

-Piston rings damaged and or improperly installed..?

-Valves not seating properly...?

-Valves sticking..?

-Check Valve Train assembly.

-Did you perform a compression test with #4 cyldiner at TDC...?

-Excessive Air escaping through the crank case points at a cyldiner/piston sealing problem.

Air escaping through/into the cooling system would indicate a damaged cyldiner head gasket and or a possible fracture/crack in the cyldiner block or the cyldiner head.

Air escaping thought the intake or exhaust would indicate a valve sealing problem.

sdoolin

Thanks for the ideas. All will be checked. Valve lash was set per the LC spec at assembly (not that it may not have moved). Since I have the head off (again) I am going to check valve seats and even valve guide clearance. I am also going to inspect the rocker arms and shafts for possible galling/sticking.

I really think it is a piston ring deal, but want to check _everything_. With #4 at TDC (valves closed) air was escaping into the crankcase.

sdoolin

Turns out loss of compression in #4 due to valve being stuck open by debri. Explanation = I had the upper intake plenum powder coated a super shiny silver to go with the valve cover. Came out awesome. However the guy that powder coated it did not mask off the TB opening, or any others. So on top of 257k miles of intake "gunk", he bead blasted it, applied the pigment powder and then cooked it at whatever temp powder coating gets cooked at.

When I got it back from him, I mentioned to him that he maybe shoulda masked it off, he said it'd be OK. I didn't believe him and did my best to clean/wash/scrub/clean/wash/scrub the inside of the thing before I installed it. Don't think I got it clean enough and figure something dislodged from the upper plenum and stuck the valve open. The valve seat was a mess and so was re-cut.

That super shiny silver upper plenum now barn-art and I have installed a spare (not so shiny) one.

Engine running strong, very good power above 3400 RPM, runs out of steam at just over 5000 RPM. I had hoped for a little more in the low end.

Oh and now I have the dreaded surging idle problem. I cleaned the idle control valve completely and verified no junk in the coolant lines. TPS is working, but I am running without the O2 sensor right now, it gets installed tomorrow with the last of the exhaust work. No EGR (should not effect idle).

If I can't fix the surging idle problem I guess I will be forced to buy dual webers (twist my arm)? Anyone running a dual carb setup on a street truck?

osv

the valve/seat could have been burned, if the valve was bound up in the open position, that makes sense.

not sure how it stuck open because of garbage going into the combustion chamber tho... you never actually found anything holding the valve open, right? was the head new, or at least the valve guides replaced... did the valve travel easily in the guide, when it was disassembled?

congrats on getting it running, i would not switch to carbs.

sdoolin

The head was completely refurbished. New oversized valves, seats cut to match. Valve guides inspected and clearance/replaced where needed. The valve did travel easily in the guide (when finally apart), but like I said, the seat was pretty well beat-up.

I never found anything holding the valve open, but I think that when I turned my compression tester into a quasi leak-down tool and applied shop air to that cylinder whatever was lodged became, um, dislodged. Just my theory. I wish I would have re-run a compression test after applying shop air, but then, I'm glad I got the head off and had that valve seat dressed.

Trying hard to stay away from the dual carbs, I just _hate_ the surging idle problem.

osv

if the seat was knicked and beat up, if must have indeed been a piece of metal or something :-( i've known people that have had that sort of thing happen with rebuilds and such.

whatever it was must have gotten spit out the exhaust, i wonder if it could be sitting down in front of the screen for the catalytic converter?

re: the surging idle... you have the crappy early intake throttle body, what you need is the later model conversion, that doesn't point the tb down, it points straight forward.

see if the surging idle problem goes away, when you swap the tb/plenum out.

that looks like a clean truck, hang in there!

sdoolin

Another update...

Discovered late last night that the idle adjustment screw ( large screw on passenger side of TB) was backing out while I was driving it, so needed a new O-Ring. Did that and re-installed. I am pretty sure this had something to do with my surging idle problem.

Today I had the exhaust system finalized, I was running just the header, a straight pipe, and a Magnaflow muffler for the first 100 miles or so (and no O2 sensor). So today I had a high flow CAT installed, along with the rest of the overall system and tailpipe (with cool chrome tip) and the O2 sensor.

Couple of thing to note. First the surging idle problem is GONE! She revs and runs out and drops back to a nice 950 RPM idle every time (EVERY TIME). Please knock on wood for me, I just did.

As for the power, installing the high flow CAT seems to have eased the power delivery somewhat - which I expected, but it has also moved the power band ever so slightly down the rev range. Before the CAT I could really feel it come on the cam at 3600 RPM. Now I don't get that surge at 3600 RPN, rather it starts to build earlier and just drives right through. The guys at LCE told me this would be the case, and my local exhaust guy agreed.

So, with all of the mods listed in my original post (top of this thread), and with the buckets of money I spent at LCE, I am a happy camper (knock on wood again please). This 4Runner will now go 0-60 in about 8 seconds (measured by counting 1 Mississippi, 2 Mississippi, etc), and pulls strongly in all gears. Spent a few minutes up on the highway today and fifth gear roll on passes are much better. Not like my 911, but much better. Power band is from about 3k - 5k, pretty much where I wanted it. Downshifting to 4th is not required, she pulls well in 5th. I plan to keep this thing till I die (hopefully another 20 - 30 yrs) and have no interest in a contemporary SUV, so I am good with this.

I have read some bad things about LCE on this and other forums, mostly having to do with price, and value for money, so I will say (for now) I am happy with the results of the build. Yes, it was expensive (VERY), but I got pretty much what I thought I would out of the build.

I guess I should change my sig to say fastest 4Runner in the tri-state area (and most expensive).

As for the rest of the truck - I am the second owner, I purchased it from a guy in Dallas 6 yrs ago who kept EVERY receipt and I even have the original window sticker. She needs a little body work here and there, and I gotta re-install the AC, but other than that she is a creampuff.

Cheers and I am out....

Kiroshu