Question on replacing the cylinder head 2.7L

So I'm an idiot, had a head gasket leak, but i took too long to fix it and ended up with no compression. Took the head off, did some very sketchy measuring on the head mating surface, and got about 0.017 in gap, so the head is definitely toast. As I am an idiot, and this is my first time doing anything like this I have a few questions.

Should I reuse cams, lifters and rollers? From what I can tell the valve cover mating surface still seems flat, and I put the cams back in without rollers and spinning them is smooth, no binding or anything, so I'm assuming they're not bent, would it be okay to reuse them in a new head?

Could I also reuse springs and valves? I can't imagine these valves would seal up very well with a new head.

But is it even worth it to replace in the first place? Im afraid there's just going to be other things that got damaged from overheating it and I'm not trying to do this again. I would love to grab an engine out of the junk yard for the same price I'm about to spend on a new head, but I can't find anything anywhere.

What are your thoughts?

 

I'd start with getting a accurate measurement of the gasket surface, just to be sure if it's toast or rebuildable.

 

Yes re-use everything. Even headbolts. Just replace gaskets.

Heads are very expensive, they are milled all the same so any cam fits any head, but these are good questions.

Getting it measured at a machine shop for warp and getting their opinion would be a good start.

 

Well I measured it with several of the straightest things I could find as I don't have a straight edge, but using feeler gauges, all of them averaged around the 0.017in.

I might still get a shop to confirm it, but assuming it's right, can that even be machined? I heard these engines don't like being milled as it messes with the timing too much. Plus at this point it might cost just as much as buying a head.

 

I would have to disagree with you on one point. These head bolts are torque-to-yield style bolts and it isn't recommended at all to reuse them as they many times can "stretch" as that is their design. A set of bolts is not that expensive, and when it comes to something engine-critical, why risk such a thing?
Other than that point, I agree that a good idea would be to take the head to a machine shop. The cost of having it checked-and-decked isn't that much, and they can also make sure the valve train is in proper working condition. If the tappets need a different spacer due to wear, they can take care of all of that for you at the machine shop, and save you a lot of headache. I know when I did the head on my 2.7L I spent more time than I cared to getting the correct shims on the tappets. At least this way, if the machine shop does the head work, the OP would know it should be good to go.

 

spot on.

Even if you buy a used head you will still want to have it checked and inspected by a machine shop. Might as well use what you have.

 

Right there.. you NEED a machinist straight edge to get a good measurement. If you are seriously considering NOT replacing any of the one time use hardware, you are setting yourself up for failure.

 

I agree do not reuse one time use items such as the head bolts.

Unless you like doing it again...

 

What's considered one time use hardware? As far as I was aware head bolts and head gasket were the only true one time use stuff

 

Depending on the vehicle, there are other fastening hardware that are considered one-time-use. Cam sprocket bolts on Ford trucks with the VVT system, etc. is just one other one that I know of. There are others.

 

I honestly am not sure about what hardware on the engine is torque to yield, I would look in a FSM or ask a Toyota parts dept.

 

Head bolts aren’t one time use. Check the manual

I’ve reused hundreds.

 

The Haynes manual just says measure and inspect the head bolts if you use them again, but I take everything in the Haynes manuals with a grain of salt.

 

According to the Toyota service manual information, the bolts "are prone to stretch" over time. Bulletins also recommend replacing the head bolts on the 2.7 as well as the 4.0 and 3.5 engines because of the risk. If you want to take the risk of blowing another head gasket to save $100, that is up to you. I would say in my professional opinion that I would never let one of my customers do a head job and reuse the original bolts.

 

Experience and factory training lead to me re using them.

The pressure on the cylinder heads simply aren’t enough to stretch them. We’ve measured them.

Nearly all head gasket failures on Toyotas are due to gasket failure or overheating from low coolant levels. Not the bolts like the old days of supra engines.

My point is they are reusable by factory standards and there’s no reason to waste money on them.

 

Doesn't matter, I already bought new head bolts before even finding out the head was warped. My current concern is being able to still use the head after milling off 0.02"

 

I get it. but why take the chance? You say you have reused them, and that's up to you. I have seen too many Toyota head bolts that were stretched and didn't pass the measurement stage. Why take a chance when working on a customer's vehicle? Why risk it? Because the one time you are wrong, you are pulling a head and redoing a job for free, and have a pissed off customer. All over a set of head bolts that for the 2.7L engine have a shop cost of $60, and are Mahle brand. It's just not worth taking the risk in my shop. Again, you can do it all day long if you want to. I'm not saying don't. But again, a $60 part that could result in a $1500 second repair cost? Save a penny, spend a pound.

 

0.020" is minimal loss of metal. It wouldn't even cause issue with the chain tensioner. I'd only start to be concerned if they had to deck off 0.10" or more.

 

Go with an aftermarket head gasket that is thicker than stock. My stock OEM Toyota gasket was .020” thick on my 2TR. When I had the head milled .010”, I bought a Mahle 54534 .030” thick gasket. A .040” thick gasket should be in the neighborhood of what you need after the head is resurfaced


For anyone else in the same boat, the better option would be to ditch the torque to yield head bolts altogether and go with ARP studs. They are reusable as well and worth the money imo
https://www.lceperformance.com/Pro-Head-Stud-Set-2RZ-3RZ-p/1024075.htm

 

Re-using torque to yield bolts is a fool's choice. The experts just use once, like they were designed to be used.