95 4 runner 3vze head gasket rebuild

So Ive tore down the heads to replace the head gaskets (had water in my oil). Sending the heads to a machine shop to get tested and repaired if needed just wondering when I put it all back together should I attach the exhaust to the heads before I install them or is it better to set the heads then come back and put on the exhaust when I removed it I could not get the exhaust off so I just took both off at the same time exhaust attached and if y'all could give me any pointers on the rebuild I would really appreciate it as this is my first time changing these gaskets

 

Well AceBoogie504,

Water in the oil would likely indicate the HG is connecting a water gallery to the oil feed ports to the heads and cams or that you have a head that is indeed cracked.

The HG's on the 3VZ-E are somewhat prone to failing as you may have already determined and that was in part fueled by the fact that Toyota had to get rid of there asbestos adorned HG's when the 3VZ-E was introduced with the late 89 early 90's model Pick-Ups and 4Runners. So there was a service recall for the vehicles that came with the non-asbestos gaskets which were not very good gaskets as it turned out. I remember my buddy Mike stopping by to say hello in Lake Forest while running up to Downey with a stake bed truck full of 3 VZ-E engine's, all with blown HG failures. I guess Toyota was swapping entire engines at one point. This was just after I had purchased my first house so that must have been 1990 or 1991. So when I purchased a 1991 4Runner in 2018 for $1,600 its FeldPro HG's let go two months after I acquired it with 237K on the odometer. Unfortunately the PO had little history for the vehicle. My answer to the HG problem was to bore and deck the block and hand lap it for MLS. I lapped the heads in like manner and replaced the exhaust valves while i was working them over. I put DT headers on the engine and installed the MLS HG's using ARP head studs instead of the bolts. The #6 cylinder gets an immense heat load due to the OEM crossover pipe and the exhaust manifolds geometry. So a header is the solution for that. The proof is that as the insulator for my #6 spark plug had disintegrated in the 2K miles I had put on that engine after I had replaced them prior to the HG letting go. Granted I was hammering on the vehicle pretty hard as I headed up the grape vine with a full passenger load when it let go. As I later determined the gallery on the #1 cylinder had made a straight path to the compression ring in the HG and it was passing coolant into the that cylinder with little resistance once the breach was made.

I have had chats with FB group members for the 3VZ-E who have preceded my experience in going the MLS/ARP route and 100K miles and driving the engine like you stole it seems to be documented as real life expectation. But getting the heat out of the motor is I think a large part in getting the reliability back for this engine. So pitching the CAT and opening up the exhaust system will help with that as well as a proper CAI with a K&N FIPK although that may just allow you to make a bit more power and therefore more heat to get rid of. I have a build thread in this web page and I have listed all of the modifications I have done to my 91 which might be worth a look if your looking to keep your 95 for the long haul?

Cheers,

ATGP

 

Yea everything I've see on the 3vzes are showing bad head gasket and overheating issues, your right most of that heat has a hard time escaping #6 I actually swapped out the radiator for a 3 row full aluminum one witch I believe keeps it a bit cooler than normal lucky my heads were not cracked I had them fixed up and all new seals and shims where needed I had a fun time cleaning off the block as it's likely never seen the light of day, I'm currently waiting for some new plug seals for the cams I'm wondering if I should put some sealent around those where the cam guards sit they had some black sealent all over when I removed them and I noticed they sit outside of the valve cover and one has the distributor that attaches too it what would y'all recommend I'm also gonna replace the knock sensor/wire, the pcv valve and grommet I guess the PO removed the hose from it cause there wasn't one there I'll also replace the fuel injectors with genuine rebuilt ones and also the pigtails going to it. While I love this truck I'm getting fed up with putting a wrench on it every week as I depend on it for work but I wanna make sure that I fix everything as best as I can before I get rid of it or stop using it as my daily. I'm looking into getting a 2005 trail blazer right now what do y'all think.

 

Sounds as though you are getting well abreast of the issues. The CAM shaft seals are a nice press fit into the cam tower/head but those stupid pugs caps that are at the back of the engine are not. The only technique that has worked for me is to have the cam bearing cap removed at the back of the head. This way you can set the cam plug into the head with a nice liberal bead of Right Stuff Gasket maker on the flanged surface. Then use Loctite 515 to seal up the cam bearing cap and as you seat it into position the right stuff will extrude out to the edge of the cam plug's flange and seal it really well to the head and upper half of the cam bearing cap. Torque the bolts to specification and it will be leak free. The cam covers are crap and I have yet to stop the ruddy seal in the groove from weeping onto the headers. I have almost 20K on my engine rebuild and am very pleased with the overall performance. I just wish it had a bit more torque and HP for the big hills. If you can swing a header I would do that before I got a Chevy.

 

Yea definitely not the best design but I guess it's Toyotas way of bringing work to their service stations. I live out in Alabama where there are a lot of hills and it really lacks power climbing those hills I've read threads that say you can advance the spark to get more power but I feel in the long run it will damage the engine I rather just keep it like Toyota engineered it, I've done everything I can to get the most out of it but I fear I need something a little more powerful because I pull a trailer to work and unfortunately I don't have have 20k to invest into it, I have another question about these two power steering lines that come off of the ps pump do what do they attach to it has some clips on the end of the hoses but I can't find anything showing where they attach I thought maybe the plenum but it doesn't really make sense to me. I had a pretty good leak on my ps pump so I went ahead and replaced all the seals on it but I think it's still wearing where the spindle attaches also I couldn't get the bolt off I ended up having to remove the whole bracket it attaches to

 

There is a pressure switch on the power steering pump that has two nipples on it. When the pump needs more pressure the switch open up to allow a vacuum leak and that will boost the idle speed to allow the pump to make more pressure. Only happen at idle in a parking lot doing full lock turning with out rolling the vehicle's tires.

 

just did a 93 a few months ago at work.. the way we do them is put both heads on at the same time, manifolds installed already and the y pipe loose. takes a few people.. but it worked well.. its how the guys would do the recall back in the day

 

So Ive finally got the truck completely put back together and now I'm having a issue of getting no spark I've checked almost everything replaced the ignition coil and distributor to no avail I'm getting fuel from all the forums I've read it could be a relay, my ECU, even the maf wondering where I should start I checked my timing and it's perfect just wondering if the cams are supposed to be top dead center when I install the distributor and if not would it cause no spark

 

Been a long time…any update? Considering buying a 91 with head gaskets blown already. Willing to do the work just wondering if it’s worth the $2,500.

 

I would say no unless the body and frame are in perfect condition.

 

It doesn’t look perfect. It has 75k on a rebuild too which to me is odd it has a blown gasket unless it was abused….