93 Toyota 4x4

Just a little back ground info on the truck, 1993 22RE with 123,000 miles. No excessive valve train noise. Recently had an exhaust leak and had trouble sealing it. Had the manifold resurface and installed the gasket but it still had a slight tick. So I torqued the header bolts down a little more. No more than 10 ftlbs over spec. Is this enough to split the head at a water jacket??

After the replacement of the gasket I noticed a slight miss at cold idle, then after the truck warmed up it went away. This happened every now and then. The last day I drove it (about a week after the replacement of the manif, gasket.) about 40 interstate miles, the idle dropped to about 600rpms and very weak. Normal was 8-900rpms. Drove on into work. After cooling off for the day. it was started and idled with a slight miss again. But not 3 minutes latter the truck started pouring out white smoke out the tail pipe. This only got worse as the truck warmed up. I drove it to the closest parking lot and shut it down. The dipstick was slightly discolored but not milky. The valve filler cap had a slightly curdled oil on it, plus there was water dripping out the tail pipe.

The oil has been drained and a little water was in the oil, not tons of water but some. Antifreeze looked as good as new.

I've been pulling parts off, but haven't got the head or timing cover off yet. Did notice under exhaust port #6 some moisture which wasn't there before. Where or how does one look for a small crack as I'm afraid it won't be visible. Of course I don't want to replace the head if not needed so I need to make sure that this is the source of the leak.

I'll try and post up some picts.

93 Toyota 4x4

Here's the picts, spark plugs look good as do all the exhaust ports, just #6 still looks like it had an exhaust leak.







see the leak at the rear, since the ports look normal this kind of makes me think tightening the manifold bolts down to much might not be the cause, so HOPEFULLY it's just a head gasket

Bigblock

We put all our head bolts at 70 ft/lbs. The clean spark plug is the cylinder thats getting water in it. The gasket was ready to blow anyway so not your fault. Use a MLS gasket and let a good shop inspect your cyl head before you reinstall it. Electrolisis eats them up sometimes.

93 Toyota 4x4

Could be electrolysis as I rarely drive the truck, less that 3,000 miles per year and that's pushing it. Been driving it about 400 miles/ week for the last 8 weeks on the interstate. Nothing obvious for the leak but the back of the head at #6 has very dark spots on the gasket which just so happen to correspond to the area where the block was damp. I just need to make sure that it is the gasket that failed and not something else. The truck ran so well there should be no need to do any thing by way of valves. I would just like to have the head cleaned and very thoroughly checked. I need to be 100% sure that the issue is fixed as pulling the head is one PITA.

Not to much water in the cam cover-



No build up of nasty oil--



Guides are in one piece and look good also, but will replace with steel rails-



Suspect area of the head-

Mike_Honcho

Hey 93 Toy',

It is hard to tell from the pics (I even went to photobucket to try and zoom in), it may just be the angle of the picture but the water passage at the 3 o'clock position in the bottom picture "Suspect area of the head-" looks like it maybe pitting out into the cylinder portion of the head. This would give you bad head gasket indicators, and possibly could give you intermittent bad head gasket indicators (as the metals and gasket expand and contract throughout the heat cycle).

I am in the process of reassembling my engine now after a rebuild because electrolysis pitted out the water channels in the same spot. I realize no two problems are exactly the same but I also didn't have milky oil, and pressure, compression, and leak down testing were fine. Intermittently the radiator system would start blowing antifreeze out of the overflow from the reservoir. I was totally stumped along with every mechanic or friend that looked at it. I bought an exhaust gas tester from UView and found that I had exhaust gas in my coolant/antifreeze. This led to me pulling the head and finding the pitting.

The pitted areas on the water passages of my head were slightly more pronounced than your's but the gasket looked really good. It was starting to discolor slightly in the areas were the pitting was occuring (where the cylinder area was beginning to meet the water passage.) but it wasn't obvious on first pass looking at the head gasket alone.

I would look at that area closely and as you recommended get a machine shop to look at it. From the picture it looks like a lot of the gasket material is still on the head. Have you removed it and looked at the mating surface/deck portion of the head?

If you go for a new head I would recommend Engnbldr or LCEngineering they both seem to sell quality non-Chinese castings (Engnbldr = Argentina, LCEngineering = Taiwan?). Both have been recommended in lots of threads throughout YotaTech and ToyotaNation.

I have heard that this is caused by not running Toyota Red coolant... I know that according to the manual any coolant with the right % of ethylene glycol should be fine. I also know that when my engine is reassembled I will be running Toyota Red LL or Toyota Pink SLL coolant (haven't decided which yet), and not continuing to use the All Makes/All Models Green that contains 2EHA and silicates.

Hope this helps... Let us know what you figure out!

-Mike

93 Toyota 4x4

Wasn't sure where the failure was as I just wasn't convinced the failure was at #4. Did more research spoke with a knowledgeable person and finally found the problem. It's obvious now!! I took a closer look at the pistons and noticed #1 was pretty clean. The combustion chamber was about 50% cleaned off....i.e. no carbon. Other cylinders were just a little dirtier w/ soot. But all the valves, plugs and exhaust ports looked the same. It may have just been harder for me to see as the truck wasn't driven very far while smoking. I now look at the picts and see it easily. Luckily the head gasket was carefully removed and came off in one piece. It was easy to spot, the fire ring on #1 was split.







The plastic timing chain guides are in very good condition (123,000 miles) but are being replaced w/ steel guides. No groves anywhere. So best case scenario for the repair. I still need to drop the oil pan as it needs to be cleaned out.

So regular Prestone anti freeze is a big NO NO??????

osv

there is nothing wrong with using prestone, or any other modern antifreeze, in a 22re.

replace the head with a new one from engbldr in Oregon, search this forum if you aren't familiar with his shop.

you are replacing the entire timing chain, not just the guide? and the water pump as well?

93 Toyota 4x4

The head is good. Just had it resurfaced, water pump is fairly new, so all that's being replaced are the chain, guides (steel), gears and all necessary gaskets (Toyota), fuel filter as it's one PITA to get to when engine is all in one piece.

scuba

Yep, #1 was definitely steam cleaned!

Good luck with the repair.

86toyotaprerunner14

Thank for the link

93 Toyota 4x4

It's been back together for a while now, had two leaks, upper radiator hose not tight enough, and the coolant line under the exhaust had one loose bolt. Also had idle issues, idling at 1,200 RPM's warm, but just didn't know about the air screw adjuster. Timing was at 10 degrees and not 5. New plugs, rotor, distributor cap, dreaded fuel filter, and readjusted 3 valves. Now it idles very nice at 750 rpms, very smooth and strong.

I filled with cheap 10w30 and seafoam, and will put a couple of hundred miles on the truck then do another oil/ filter change w/ good 10w40.

Picts of the resurfaced head-



Cleaning block of old head gasket -



Timing chain in place, notice shiny link and mark on gear also NEW FUEL FILTER-



Intake and rear metal lines preinstalled before placing head, replace fuel filter before installing head!!!--



I got the top end together before dropping the oil pan--





Oil Pan Install-

The diff was dropped but the axles and drive shaft left attached. Sway bar dropped, steering damper and links dropped, cross member removed and three diff mounting bolts removed. Diff was then dropped. Oil pan removed after oil pickup removed. To reassemble.I coated the oil pan edge with grey permatex RTV which is stiffer than the Black RTV. Put a light bead on the flange and allowed it to set up for a while. It was a little firm. The strainer was dropped in the oil pan. Pan was gently put under block flanges, being careful not to touch the grey RTV on anything. Two 3 inch bolts were threaded at the back of the oil pan. These were used to keep the pan hanging down from the block and not touching it. The front of the pan was tilted down to allow access to the pickup. I could put the strainer in place with out touching the grey RTV. Blue Locktight was used on the 4 strainer bolts. Once tightened the oil pan was gently raised up to the block and loosely attached. Grey RTV was allowed to cure even longer...use your own discretion, then tightened to spec.

And looks done, but final tweaking needs to be done-