4.0 sohc engine won't fire after head gasket fix

[SteFin]

Blew a head gasket, and put on new ones timed the chains I have a set of Homemade tools I made (going to post pictures later of the tools). Engine will not fire even squirting starting fluid in Cylinders only showing 60 lbs compression and 35 on # 4. compression doesn't leak down (not going through valves. Wife did drive it 4 miles after temp gauge pegged, it did stop in Field before the Barn (my shop is in the barn) and would not start. Had Water in oil, and set for 7 weeks before I got to it. 2001 Sport sohc engine (engine is 02 and was sweet). I understand these indications are pointing to collapsed rings, after 7 weeks it wouldn't turn over with a 4 foot cheater bar on 1/2" breaker bar used a D-8 bulldozer starter and a explorer start gear and bendix and a 24 volt set up to finally free it and marvel mystery oil down spark plug holes. My cam position tool holds the cam timing/center line notches at 1 5/8" off the head surface for both of the notches with the small radius pointing down towards the engine which allows a 1 1/2" wrench to hold the flats on the cam on the big boss (behind the chain gear)in position. The 1 1/2 wrench works much better than the Ford Hold Down Tool and is a much easier way to position the cam with sprocket nut loose or at only 25 LBs torque. I have another block with good positions however why is it not firing or popping with starting fluid in cylinders and pistons installed (100k) even with 60 LBs I should be getting some noise instead of the wuy wuy wuy wuy of a free spinning engine. Am I being dumber than a road lizard and missing some thing simple and right in front of me. Thanks SteFin (a perplexed shade tree junkyard dog)

 

[stroker331]

Dose it sound like it got any compression at all?? And dose the theft light flash fast or solid? Dose the tack move when spinning over? You may have missed a cam or a crank sensor connection.

 

[SteFin]

Doesn't sound like a lot of compression if 180 were a benchmark the 60 I got sounds about right thanks again

 

[2000StreetRod]

broken compression ring?

When a ring is rusted to a cylinder wall it's usually not a good idea to free it using brute force. A safer method is to squirt penetrating oil, rust solvent or something similar into the cylinders once or twice a day for several days and then rock the crank back and forth after the penetrant has had a chance to work. I'm wondering if the compression ring is broken.

Are you sure the camshafts are timed correctly? Is there 60 psi on all cylinders except #4 ?

Many members hook up the spark plug wires incorrectly. Check #5 and #6 .

 

[SteFin]

I'm considering re-ring this motor, I have a couple other Blocks unmolested with pistons and rings installed at factory less than 100K. At TDC I locked the crank, there is a boss on the cam behind the gear that a 1 1/2" wrench will hold the cam while loosening the cam spocket. I made a cam positioning tool to hold the slotted end of the cam at 1 5/8" from the head surface to the top of the slot or notch (which is the center of the cam) short end of cam slot or small radius goes on bottom. Used marvel mystery oil and pb blaster for 3-4 days before I put the D-8 cat starter to the flywheel. inspected each cylinder and rotated engine with about 4 head bolts holding heads in place. No scaring scratching stange sounds coming from pistons or cylinders. Passenger side front cylinder is 1,2,3 at firewall driverside front 4,5,6 at fire wall Coil is marked 1,2,3, 4,6,5 plus I take a sharpie and number each end of my plug wires. I have the rubber inner wheel wells off the vehicle so I can pull and put the plugs and wires on and off in no more than 15 minutes I gonna to squirt starting fluid in eash cylinder tomorrow. plugs are firing, fuel rail is charged, ground good on ecm pats system doing 2 second blink, and inertia fuel pump saftey switch engaged (button down) I will re-check the plug wires once I did switch the sides of the coil on this very vehicle simply read the numbers then put the wires on wrong side Thanks SteFin Junk Yard Dog Shade Tree

 

[shucker1]

Plugs wet when you pull them out?

Have you tried pulling the plugs and rolling over without anything to clear the cylinders?

It might be "Rich Fouled".

If you do try it, keep the lose boots away from the cylinders. You don't want any extra sparks in the wrong place!

 

[2000StreetRod]

timing sounds good

From your description it sounds like the camshaft timing is correct with both camshaft slots as below when crankshaft is at TDC and the timing chain is taught.

I assume that the chain was only taught from the spring in the tensioner so the timing might be a few degrees off but not enough to result in your low compression readings. Did you rotate the crankshaft several revolutions before recording each reading? Did the pressure increase after each of the first three compression strokes? Did you try squirting a little oil in the cylinders to see if the compression increased? Was the throttle plate at WOT?

Why did the engine overheat and blow a head gasket? How did you determine the head gasket blew? Is it possible the head cracked instead of the gasket blowing out? You didn't answer if all the other cylinders (1, 2, 3, 5 & 6) had 60 psi compression.

 

[SteFin]

I assume that the chain was only taught from the spring in the tensioner so the timing might be a few degrees off but not enough to result in your low compression readings. Did you rotate the crankshaft several revolutions before recording each reading? YES Did the pressure increase after each of the first three compression strokes? NO Did you try squirting a little oil in the cylinders to see if the compression increased? Marvel Mystery Oil Was the throttle plate at WOT? Didn't check that

Why did the engine overheat and blow a head gasket? Plastic Tank on radiator developed leak Wife didn't catch it until 4 miles from home How did you determine the head gasket blew? Water blew by at 2-3 cylinder location passenger side and 4-5 on driver side, super cleaned head naked eye didn't see any cracks, tolerance with feeler gauge .006 tight diagonally and straight across didn't leak down any gas from valve combustion chamber Is it possible the head cracked instead of the gasket blowing out? You didn't answer if all the other cylinders (1, 2, 3, 5 & 6)yes had 60 psi compression. I have another set of heads with 100k that pass the eye test and the warp is a little high .009 both diag & straight across came off a motor with a broken timing chain guide chains were ok. No signs of overheating. Would you change the heads?Very good points Thanks SteFin Junk Yard Dog Shade Tree my cams looked liked the picture you sent small radius down 1 5/8" off head surface both cams

 

[SteFin]

I removing the plugs today air out cylinders and insert starting fluid Thanks SteFin Junk Yard Dog Shade Tree

 

[2000StreetRod]

too much oil?

How much oil was added to the combustion chambers? If a lot, did you rotate the crankshaft with the spark plugs removed to blow the excess out? If you cranked the engine with plugs installed and excess oil in the chambers you could have blown the head gaskets again.

When I purchased my Volvo 850 Turbo Wagon it had set for 1 1/2 years in a field. After I loosened the rings from the cylinders walls I checked the compression which was as low as yours. I suspected the rings were still rusted to the pistons so every day, twice a day, I added a squirt of Sea Foam (the only timed I've used it on any vehicle) to each cylinder. Eventually the rings came free and the compression increased significantly. I didn't try to start the engine until the compression came up and I changed the oil to get rid of all the Sea Foam that had leaked past the rings. I've been driving it for a couple years now with no problems, good power and good fuel economy. You might try something similar for a few days before swapping the heads again.

 

[SteFin]

I'm a big believer in Sea Foam first became a Fan when the Junk yard boys added it to gas tanks to dissipate the water. Buy some tomorrow We always add add about a 1/3 of a quart oil total on top of both heads to make sure the valves cam and springs are well lube always with good results. So far added three squirts of Marvel Mystery Oil with my squirt can probably a tablespoon. The plugs were not oil soaked or fouled and the compression guage holds compression with out leaking down. Thanks SteFin Junk Yard Dog Shade Tree

 

[sangeej]

what does the home made timing tool looks like? thanks!

 

[bigred4x4]

Maybe consider getting the heads magnafluxed ? That way you can eliminate that issue. I rebuilt my motor (re ring) after a hydro lock and is running good but the original engine was replaced after a severe overheating leasing to low compression. I'd probably pull it and start over if it were me even 60 psi even cold is pretty bad it should be two to three times that . Try a bore gauge on the cylinder and a feeler gauge to check ring Gap id be willing to bet the problem may reside in the block and not the heads unless there cracked.

 

[bigred4x4]

Although it should at least try to start I'm guessing a timing issue for a no fire condition.