4RunnerLVR86

I just bougth a 86 4Runner and the timing chain jumped a tooth or that is what I was told by the previous owner. I installed a new chain ETC.... I'm not sure if the cam was in the correct position when I lined the dots up to the bright links on the chain. Would the cam shaft be 180 degrees off cause no compression on all 4 cylinders? Also I was told that the pistons never hit the valves and as I rotated the motor nothing seemed to be hitting but it didn't take that much force to rotate even with all 4 spark plugs in. Tell me what yall think about this. Thanks for any help.:pat:

ovrrdrive

People that say the 22re is not an interference motor are full of crap.






That's what happened to my valves when I jumped time. All 4 intakes were bent. I can't say for sure that's your problem because I don't know how bad yours jumped, but it is definitely a possibility.

If it's 180 out there would still be compression btw. It just wouldn't start.

When you say no compression, is it just spinning over really fast when you try to crank it and sound like the engine isn't turning over just the starter?

And you tried a compression tester and get absolutely 0 on all cylinders?

If so I'd really be inclined to think you have trashed valves...

GrimReaper

180 is an ignition timing to valve timing problem. Taking the distributor out and spinning the motor one turn and re installing the distributor is all that it would take to correct.

It will still make compression fine when testing.

Try another compression tester. Even with bent valves like you would get with a broken timing chain you will get some compression. I burned the valves in my Supra BAD from a leaned out injector and it still could make about 30 psi on the starter.

ovrrdrive

That's not true...

I had zero compression on all 4 cylinders when I smashed my valves. Look at the pic from behind the valve I posted. Do you really think with a gap that big it will read any compression at all?

You really shouldn't give advice about things you don't completely understand.

GrimReaper

If the starter is spinning fast enough (plugs out of all cylinder not being tested throttle propped fully open battery charger going...the way its suppose to be done) it should bounce the needed some and show something. You don't make 170psi on a 4 inch stroke without some serious CFM being generated. 30 is still piss poor and shows a horrendous problem.

Bottom line is it is FLAT out stupid to just jump into ripping a motor apart till you rule out a problem with testing IE a bad compression tester. Since most are $15 jobbies from vato Zone I sure as hell wouldn't trust one without a second test especially if the test was not performed correctly.

I DO NOT subscribe to "guess and spend auto repair and advice". I am not about to tell somebody, I don't know, who has tools I may not trust and skills that may be marginal to go rip a head off a vehicle without further checks. You may be comfortable giving that sort of advice but I am not.

Flash319

Even if the cam is out you will get compression at some point along its travels. Sounds to me like your head is screwed. What I do to check a cylinder is to pull the plug, make sure the valves are closed by looking at the cam lobed, then blow compressed air into the cylinder through the plug hole. If you hear air coming out of somwhere it is not soposed to( intake, exhaust, rad) you know where your problem is. I welded the bottom of a spark plug to a air hose coupler then just screw it in the plug hole. Just watch yourself because if the cylinder is sealed the engine can turn over a bit.

GrimReaper

Poor mans bleed down test!

Thats actually excellent advice. Thats what I did with my Supra when I burned the valves. The compression tester most parts stores sell with the hose has a 1/4 air line fitting that you can hook right into you air hose. There will be a Shrader valve (same one used in your tire valve stem) you will need to remove but it works like a charm.

You may need to set the motor a couple degrees before TDC and put a breaker bar on the crank pulley to keep the motor from spinning if your truck is an Auto. If its a manual chock the wheels and put it in 3rd. 50PSI will spin the motor to the bottom of the stroke no problem if it has any seal and you don't lock the motor down. There is a little valve over lap at the bottom of the stroke so you have to have it part way up on compression to do this test with good results. Some leaking you will hear is normal its the wide open gush you don't want to hear.

There is an actually set up for this available from Summit. Look it up under "Bleed down"

dcg9381

It's pretty hard to get timing that far off... 11 o'clock position on the cam, TDC on the bottom end.. Where's the rocket science?

If it bent valves, you might not have any compression.

You could do a leak down test, but it's going to be your head in every case that I can think of.

ovrrdrive

Look, no matter how you decide to try to sugar-coat what you said it was just wrong. Sorry I come off so directly, but I call a spade a spade when I see it.

How do I know you can have zero compression with bent valves?

Because I saw it with my own 2 eyes on my own engine in all 4 cylinders that's how.


I suggest that first you learn how to read other people's posts, then you can work on comprehending them. I never said any of the things you are insinuating I said.

And his tool set and mechanical ability are absolutely none of my concern honestly. If he feels that he is incapable of doing the repair himself, i trust he will take it to a shop.

Btw, welcome to the forum. Nice start.

4RunnerLVR86

Well today I hooked up teh air compressor to spark plug hole 1 today and was leaking out of the throttle body so I'm guess intake valve #1 is bent. Ovrrdrive did your pistons get scerwed up when it hit the valves? Thanks for all the help. Also if anybody has a 22RE head they want to sell in working condition. PM me or post it.

ovrrdrive

My pistons were fine, and still are fine.

However, My timing jumped because th eplastic guide broke in half and went through the bottom gear when I was trying to start it up. When the timing jumped, the gear spun a few times and the valves hit during that time.

If your motor was running when it hit you might not be as lucky as I was.

Sorry about your luck man... Sounds like its time to upgrade.

4RunnerLVR86

I bought it like that. All I was told was the timing jump so I'm not sure but when I took the timing chain cover off the plastic guides where broke in half. Thanks anyways.

CopenHagen_Smokeless

seems to me like its a bent valve

4RunnerLVR86

Well that sucks

Lunnzz

My truck jumped time, bent all four intake valves and I had zero compression..I also had marks on top of the pistons from them hitting the valves..

ToyotaGuru

They always bend the valves. No compression = bent valves, and from
my experience the pistons have also been damaged.

4RunnerLVR86

If my piston have been dented from the valve can I still use them?

AH64ID

Would you really want to? check out www.engnbldr.com he has a master rebuild kit for pretty cheap, good quality. Get some new valves too and slap it back together.... I would take the block to a machine shop and have the bore measured before you order the new pistons to make sure what size you need.

dcg9381

If it just left a mild impression, you could use it (IMHO) - The lower end is a lot stronger than the upper end... As such, the valves lose.

BTW, whoever sold you that motor either didn't know or wasn't telling you the full story. Jumping a single tooth or two won't cause this problem..

Buy engnbldr's valve set.. They'll be cheaper than OEM, stainless is better, and they're .5mm bigger... Have the head decked and the ground for the valves.

ovrrdrive

Engnbldr SS valves are 1mm bigger.

I forget the exact measurement but I checked them against the stock valves and they were a full mm bigger.