lalojamesliz

I finally got around to a compression test on my 87 22r with 160k miles. Engine at operating temp and throttle wide open. I just adjusted the valve lash and re-checked #3 earlier today.
#1- 160
#2- 165
#3- 140 (added oil to cylinder but no change in psi)
#4- 155
It drives good but not much power. It does have 90+ hp though lol
The vacuum is at 15 @ 800rpm
My distributor vacuum advance won't hold vacuum, neither port on the vacuum advance.
I was going to spend $240+ for a new distributor with the vacuum advance, head gasket, arp head bolts/studs, water pump and timing chain kit but I'm worried it will be a waste with a engine with a low compression cylinder.
I hear a metal rattle sound between 1500-2000 rpm and I think it's the chain. I looked at the straight guide when I had the valve cover off and it wasn't against the chain but it didn't look broken.
Would you guys put more cash into a engine like this?

cbr600rx7

That's not to bad for a well used 22R #3 is only a little and notenough to justify a bottom end rebuild IMOP. You could also have carbon build up on the valves causing your compression to be lower. If you are dedicated to pulling the head then take it down to the machine shop and have them vacuum test the intake and exhaust ports. If #3 shows low vacuum then that was probably you problem. Since your doing ARP head studs you might as well have the head surfaced and the valve bowls cleaned up any way.

lalojamesliz

I was thinking of the carbon buildup too. I haven't tried using seafoam but I've heard good things about that stuff. I might try that before messing with the head.
I was thinking about the head gasket because of its age and I don't want it to fail on me

cbr600rx7

It will not remove hard carbon deposits off of valves. It takes soaking and a wire wheel to get it off.

lalojamesliz

Well crap.....

84sr5yoty

Check valve clearances on Cyl 3. Valve lash has a very pronounced effect on compression #'s.

No need to replace the entire distributor over a failed vacuum advance can. It's a simple and quick fix.

lalojamesliz

I re-checked the valve lash already. I may have it a little tight for the .008 or .08 whatever it is on the intake.... I'm going to do the timing chain very soon and I'm not driving my truck so I'll loosen it a little when I open her back up.

Can I repair the vacuum advance? If I were to buy that alone it's like $140! A new Cardone dizzy is $80 with the vac advance....

84sr5yoty

Wow, I couldn't believe a vacuum advance can would ever pull down that kind of green until I looked it up myself. It appears a new (most likely rebuilt) $80 distributor is certainly the most pragmatic choice.

lalojamesliz

It's hard for me to believe that too. I was about to buy it but now I'm tied up in replacing my timing chain, water and oil pump.
It drives great the way it is but I know it could be better with a vacuum advance that works.

fierohink

2 suggestions:

1) loosen the rockers for #3 and redo your compression test to see if your numbers improve. If a valve is too tight as it heats up it'll grow and stay open.

2) with the valve cover off you can look down the drivers side of the timing cover for the guide and chain and see if you are wearing grooves into the cover. This could be you mid rpm rattle.

lalojamesliz

I'll try #1
I'll check#2 but I already bought and received my timing chain replacement stuff

lalojamesliz

Leak down test results:
#1- 23%
#2- 24%
the one I was worried about #3- 40%
and as a surprise #4- 20% but air was coming out of the radiator
#3 was the only one leaking from the exhaust pipe. The others from the oil filler cap.
Im lot on what to do right now.
would the engine be ok if I just changed the head gasket and ran it with the #3 exhaust valve leaking?

cbr600rx7

If your doing the head gasket have the valves done. It's not that expensive. All they are doing is cleaning and re seating them.

lalojamesliz

I was thinking of that also. I'm just debating on having it resurfaced......
I'm sure if I buy the valves it would be less than if I had the shop replace them. On rockauto they range between $4.14 to double that for the sealed power valves. Do you think the quality is actually better?
What about the headgasket, I know the oem should be the best but any decent brand should be fine right? Same question for the headbolts

cbr600rx7

You don't need to buy new valves. (Machine shop will clean and re use them)
Your head needs to be resurfaced. (You are stupid if you don't)
The valve seals need to be replaced (they are cheap)
You need to check your valve lash on all valves ASAP.
Use OEM Toyota head gaskets. (If installed right they will last a long time)
Use OEM head bolts. (LCE offers a good price on them)

take le your head assembled to a good machine shop. For cleaning, inspection, disassembly, cleaning the valves, and resurfacing you will probably be into it $150-$250. Add your cost for gaskets and misc parts and if you do the labor your probably talking about $400-$500 total. If you keep trying to cut corners you will pay.

fierohink

Your motor has 160k on it. For a little more than what an inspection/cleaning and valve service cost you can buy a brand new engnblr head.

http://www.engnbldr.com/toyota-heads.html

And if you buy the gasket kit and bolts they usually give a break.

I used their stock mill and their oversized valve mill and was thoroughly happy with both.

lalojamesliz

Called a shop by me and $45 to resurface
he also told me $300 for a completely rebuilt head with new springs, seals, resurface, pressure test, ect.
I'll have to think about this one

scope103

I my opinion, the most important job the machine shop does on the heads is re-seating the valves. Cleaning and inspecting is nice, and doesn't cost (or add) much. Resurfacing is not necessary if the head meets spec http://web.archive.org/web/201211101.../7cylinder.pdf (p.22) (that's why the machine shop has a straight edge and why Toyota gives a spec). Every time the head is surfaced, it raises the compression slightly, so you can only do it a few times (of course, if your head is already spec-flat, they don't need to take off much to make it look purdy. On the other hand, if its warped enough to "need" it, they have to take off more).

Pressure testing (for cracks) really has to be done.

According to Toyota, head bolts do NOT need to be replaced. http://www.toyotaparts.metro-toyota....T-EG98-002.pdf Of course, that TSB was written when our vehicles were only 3-10 years old, so if it makes you feel better to put new head bolts in now that they're 20+ years old, it's up to you.

But, in the end, that shop is working on your head onesy-twosy. EngnBldr (and other vendors) get a truck-load of heads and preps them one after the other. The cost difference is so great that EngnBldr can often sell you a rebuilt head for less (or close) than having yours done by your local shop. I had my heads (3VZE) done by a local shop and was very happy, but if I ever get to that point again I think I'll just replace them.

osv

the question here is, what is the condition of the short block? throwing money at a head/valve replacement could be false economy in the long run, been there done that.

i seem to recall you mentioning that the p.o. didn't appear to have done much maintenance to the truck, it was basically abused when you got it? i wonder if the timing chain had ever been replaced, is the guide still intact? if he never changed the oil, the rings could be worn.

if the guide is still together, i would be tempted to get a used distributor from the junkyard, and just drive the thing 'till it drops, but also start looking for a used motor or even a core motor to rebuild, in the meantime... something that hadn't been overheated.

bakersfield is flat, you aren't going far right? just get aaa tow insurance.

lalojamesliz

That's a lot of great advice, thank you scope103