coltonstewart

I feel retarded af for this. I spent the summer rebuilding my truck head gaskets up plus a few other things. The heads gaskets were melted was the reason for the rebuild. New gaskets, lapped valves, new seals, the works. I get it all put together the best I can and then - my dumbass puts a single use lucas fuel treatment into the gas tank and then fired it up. It blew this white smoke, that smelled like oil, all out the exhaust and was running nasty while open throttle at 4000 rps to keep it from dying. I witnessed sparks coming out the exhaust when I decided to shut it down. It was decently hot but not extremely, but was only running for 2- 3 min.

I thought crap, my new gaskets didnt seal, but since then I realised - That I didnt have any fuel at all in the tank, and it was running on pure fuel treatment!!

So I put some fuel in it, and it still runs poor but no white smoke anymore. It misfires and knocks like once a second intermittently, only at low rpms though. Ive checked my timing and distributor rotor position, vacuum leaks and tubes placement, the plugs are new. The plugs are black with oil and alot of unburnt fuel on them. Tomorrow im gonna check the distributor and coils.

Sad part is, I checked compression today and it was indeed low - around 120 - 130 psi, with noticable compression difference with oil added.

Did I Burn up my piston rings with that pure fuel treatment s#!+? Are these engines drive-able with 120 psi compression? Any ideas?


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92 Pickup 4x4 3.0 3vze

HalG13

someone correct me if I'm wrong but usually the bare minimum to run a engine is around 100psi, with 120 I think your still good, little low but ok. Have you set your timing correctly and made sure firing order is right and no crossed wires? order should be 123456, no 1 cylinder is passenger side most forward cylinder (close to grill), so 1-3-5, driver side 2-4-6 with 2 being most forward as well for the 3.0

robertd33

my compression
5=80 6=170
3=120 4=110
1=90 2=120
but hey... i've got that 1 good cylinder, right?

if it runs like it is, i would say drive it for a while & see.
if the engine was out, i would probably say take it apart & check everything.

toiyodah4WD

Try Restore. I have used it for a year and it has increased compression and I guarantee it will do no harm to the 3VZE

toiyodah4WD

I would not use it in a "modern" engine. A VVT engine for example

coltonstewart

Sorry to resurrect a dead thread but for posterity I thought I would add (despite the embarrassment) that the reason for these symptoms was caused by me forgetting to install o-rings on the ceramic fuel injector seats. Yeah.. Also the sparks were due to the extra heat and flow burning out head gasket particles in the exhaust system

rattlewagon

Awesome that you updated your thread with an answer.

Are you still running the same engine? How is it going almost 4 years later?

gyates93

Thanks for the post - I just did my top end rebuild with the motor in the truck (380k km) and I really feel for you. It was a lot of work and I was very tired tracking down the small issues after reassembly.

coltonstewart

She still purrs and everything engine related is fine. Only problem is that stubborn leaking valve cover, I never have been able to fix it all the years Ive owned this truck. I think the FSM and Chiltons confuse people into putting RTV all over the head mating surface, particularly in the corners. After watching mechanics install a few valve covers, I noticed that its an old timer trick to use RTV specifically to hold the gasket in the cover during intallation, not to actually create a seal.

scope103

Oh, cmon! The manual even has a picture to show you the four tiny spots that get RTV. http://web.archive.org/web/201208130...68cylinder.pdf page 80 The RTV (called "seal packing" in the manual) has nothing to do with "sticking" the gasket, and everything to do with sealing. (The RTV goes onto the head/cam bearing, but the gasket is placed into the cover. THEN you put it together.) You absolutely need that little bit of RTV in the corners.

BUT ... I've noticed that RTV really doesn't like to stick to oil. You need to get the cylinder head/cam bearings and cover, where the RTV touches, squeaky clean. I use paint thinner; brake cleaner might be a better choice. Give it a try!

2ToyGuy

I only have the '87 22RE 4Runner, and 22R LB P/u engines in my trucks, and I know they aren't related other than being Toyota engines, BUT...

I heard a little trick from a mechanic out at my job (I'm an electronics tech by profession) who loves the Toyota engines (he had a short-bed 87, 22R engine). He said to use a little bit of "peanut grease", the very thick, sticky grease that looks like peanut butter, in the channel of the valve cover, where the gasket sits, to hold the valve cover gasket in place while re-installing it onto the engine. A tiny dab, like a tooth-pick size "scoop" in a few places around the channel in which the gasket sits. It works well too.

I do that whenever installing a valve cover gasket in either of my trucks, and I've never had any trouble with the gaskets leaking, falling out during installation, whatever. I do use the correct RTV in the places recommended by the FSM. I got one with my 4Runner when I bought it from a guy that worked at the Toyota dealership in Yuma. On the half-moons, the little gaps in the head, and so on. No leaks, as long as I stick to recommended valve lash alignment schedule, and I do.

I bought my pickup in 89, and the 4Runner in 97, and have had them both ever since, so I've done the valve cover gaskets more than a few times, both still run like a dream, too.
Pat☺

coltonstewart

Ive followed the FSM exactly like that each time (like 4x) Ive sealed the valve cover and head caps cam seal and all that , taken special care to let the RTV cure before full tighten, using Silicone Black. I take care to use the right torque specs and tightening sequence. I have even on this last attempt presealed the brand new gasket into the valve cover with RTV. So idk why it leaks every time Im just throwing ideas around, Im certainly open to tips

Co_94_PU

iTrader: (-1)

I'll hazard one guess which is a common cause in lots of builds, pay the $10 for an OEM PCV valve it's worth every penny compared to the plastic crap you get at the big box parts store.. That plastic PCV valve you get at the parts store for $3 has an "Interchange" cross over with countless engines where the part you get from a dealership "interchanges" with a few years at most..

This leads to crankcase pressure pressure that shouldn't be there or should be taken up by the valve...

You may have heard "tests" like shake the valve if it moves back and forth it's fine, and that is just not the case. This shake test just tells you the valve is not stuck in one position, it tells you nothing about how well it seals when it should be closed nor at what pressure it opens at.

Other important factors are how you torque the valve cover down and the quality (specifically the elasticity) of the VC gasket. Think about the halfmoon seals, these create a hard 90° angle on each side you are asking the VC gasket to confirm to this is virtually impossible for the gasket to conform to because if it (the VC gasket) was ductile (soft) enough to make this 90° bent it would squish out of the valve cover at the slightest of pressure.

This makes the amount of filler used, and the slope needed, on the half moons very particular to the valve cover gasket as well as the fastener torque.

.. Bottom line

If it leaks you need to put some thought in to how and why. Did you use enough filler? Did you get the right slope on the filler? Is the gasket deformed? Exactly where and why did it not seal!

You say you used the right sealer and have good specs on the valve cover (nuts?), at some point you need to consider the gasket used. Who made it, is it in the proper place, has it been damaged, was it "cold" when you put it on, etc...

Your account of "sealing" the gasket to the cover might even be biting you. It should hold in the groove without any help and sealer can cause high and low spots. This brings up two scenarios off the top of my head, your sealer is interfering with the gasket seating in to the slot like it should (thats five ?, right angles , plus your goop the oil has to flow passed for it to leak over the top of that seal, much more likely it's flowing passed the flat plane of the head to gasket surface..). A good gasket will fit snuggly in the grooveand not require any "help"

Co_94_PU

iTrader: (-1)

You mentioned before something along the lines of "I used xyz fuel treatment" and "caused part of the head gasket to create sparks out of the exhaust"..

​​​​​​The only part of your head gasket exposed to the combustion chamber is what's called the fire ring. If your melting and expelling this portion of the gasket, it needs a new gasket and you likely burnt a valve or two also which your compression test reaffirmed.

coltonstewart

Sorry this is an old thread. I did indeed change the head gaskets along twith many other things. Your post was helpful for my brainstorming, actually, because I do remember the VC gasket being part of a huge cheap gasket kit along with the HG. It looked small like an OEM and was not the most elastic of rubber. I will also look into the PCV, thanks!

gyates93

​​​​​​I did my VC gasket once for a leak and once when I did my HG, both times followed FSM exactly and had no leaks! Make sure the mating surface is very clean (brake kleen) and maybe check the plastic VC itself for damage?