I re-did the test, several times on each cylinder. The results are:
Cylinder 1: Bleeds down slowly over 2-3 minutes. Can hear some air at the oil fill port.
Cylinder 2: Bleeds down in about a minute. Can hear air flowing, but don’t know where.
Cylinder 3: Bleeds down in about a minute. Air comes out cylinder # 4.
Cylinder 4: Bleeds down in less than a minute. Air comes out cylinder #3.
I guess this is a bad head gasket and/or cracked cylinder head?
Edit to add: I re-did Cylinder #2 a couple more times, and the air comes out the exhaust pipe.
I notice you didn’t tell us the percentages of leakdown . . .
A leakdown tester will have a gauge with a scale . . . sometimes color-coded
I’m going to be extremely blunt
This 2002 Daewoo is worth next to nothing, in spite of the relatively low mileage
it doesn’t even rate the cost of an engine repair in a shop, in my opinion
It certainly looks as if the head gasket may be ruptured between #3 and #4 cylinders
If you were to have the cylinder head off and use a straight edge, I’d say there’s a pretty good chance you’ll discover the warpage exceeds the allowable specs, meaning it needs to be machined in a shop
But like I said, I don’t think it’s worth it at all . . . not for this car
if you were to do all the work yourself and discover the head isn’t warped beyond specs, then I’d say sure, throw a head gasket at it, since your labor’s free
This is the Maddox leak-down tester. The input and output pressure gauges are the same, 0 to 100 PSI. All of the cylinders will eventually bleed down to 0 psi.
This will be strictly a DIY project, though I am either going to pay for a remanufactured head, or for machine shop labor to recondition the existing head. I assume the machine shop labor will be around $350-400 to include clean-up and checking for cracks, resurfacing, checking the valve springs, replacing the valve stem seals, polishing the valves and valve seats. I paid about $350 to have this done a few years ago on an 8-valve head. I realize this one will be more.
I suspect the air you hear out of the oil fill port is air escaping past the piston rings on that cylinder.
Agreed there is likely a head gasket breach on 3 and 4. Given the air hissing out of the exhaust pipe this likely means an exhaust valve has given up.
You could have the head reworked but what might happen, and likely will, is that making things right as far as compression due to the head will increase the blow-by in the cylinders.
Reman heads at AutoZone show to be 500+ to 800. EBay shows some remans at 375 with free shipping. The eBay route is the only one I would even consider if you choose to rework or replace the head.
Are you dang sure the cam timing is right?
As a quick check turn #1 to TDC on the valve overlap (end of exhaust stroke, beginning of intake).
Intake and exhaust valves should be equally on the verge of opening.
If cam timing is corrected it might run well enough to drive on for awhile, in spite of the other issues.
I didn’t carefully read the whole thread, so my apologies if this has already been covered.
I am trying to take the engine apart now, and I am stuck at the step where I must relieve the tension on the timing belt. This engine uses a water pump which rotates to apply tension to the belt. The bolts are recessed (allen head?) and assuming I do get these bolts loosened, I am struggling to see how I can rotate the water pump. This car is very difficult to work on.
I wish I was. There is no actual timing belt tensioner, of the type that one would see in most vehicles, i.e. a metal casting with an idler pulley and either a spring or hydraulic piston which exerts force on a lever arm, applying tension to the belt. Or even a rudimentary tensioner which rotates into place, such as was used on the Chrysler 2.2/2.5 SOHC engines.
On this engine, the water pump itself is used as the tensioner. Two screws, which are recessed behind the rear timing cover are loosened, then you are somehow supposed to use a 41mm crow’s foot to rotate the water pump which then applies/relieves tension on the belt. The problem is that the water pump doesn’t have a 41mm hex anywhere to grab onto–it has splines on the body casting, behind the non-removable cogged drive pulley.
This is an incredibly stupid design, together with the fact that I already had to remove the power steering pump–remove it, and let all the power steering fluid leak out onto the belt, ruining it–not just unmount it and set it aside as you’d do on most vehicles with a timing belt. This is per the official instructions in the factory service manual, not something I decided to do on my own.
Due to the fact that I have no way to properly set or relieve the tension on the timing belt with any tool that I own, or am aware of its existence, I do not see that I could ever re-time this engine and put it back together to drive. I will probably just take my tin snips and cut the belt (since it’s already had power steering fluid and coolant leak onto it) so I can pull the head for educational and entertainment purposes, then call a junkyard to haul this vehicle away. I do not want to spend money on machine shop work and incidentals, only to discover that I cannot actually put this back together so that it will run.
Edit to add: There are actually 3 screws holding the water pump in place, according to this picture which I found online at a website which sells the OEM tool.
Yeah, at this point I am debating whether to continue trying to fix this car or go buy another one today. I can get the tool online for about $50 delivered. Still, this is the most difficult car I have ever worked on…
I appreciate everyone’s enthusaism for this car! Anyways, I was able to locate the third allen bolt and release the tension on the timing belt, and complete the disassembly. Other than having to change the sequence of some steps due to no lift, and to reach under the intake manifold and cut a heater hose, due to no access from below to disconnect it from the heater core, it was not too difficult. Obviously, upon reassembly, I will connect a short length of new hose to the cylinder head prior to setting it down, and then use a metal coupling and two hose clamps by reaching under the intake manifold.
So now it’s time to order the parts I need, and the specialty tools needed to do the job properly. I can’t believe the OEM head gasket is made of cardboard and the only metal part is the fire ring around each cylinder. The exhaust manifold gasket was MLS, and the intake manifold gasket was perforated steel with soft graphite, but the head gasket was made of the cheapest possible materials.
I am debating whether to buy a reman. head online or take this one to a local machine shop. I am also debating whether to buy a professional torque angle tool, as I am sure I will need such a tool many more times in my life. The kind of cars I like to drive are getting old enough that head gaskets will need to be replaced due to normal wear and tear.
You got the head off and found the problem. Given the age, make, and questionable long term reliability (sorry) of the rest of the car, I wouldn’t do much more. Buy a machinist straight edge and a set of feeler gauges and check the head surface. If it’s out of true by less than .007 I would simply reassemble it and drive on. If it is warped I would have it resurfaced and nothing more.
Composite head gaskets like yours were the norm for 50 years, there’s nothing wrong with them. The fire ring is the important part, as you can see.
Unless the torque procedure includes some odd angle like 135* I would skip the angle gauge too. 90 degrees can be easily accomplished by a punch mark on the bolt and a protractor (or the naked eye).
So today, I finally ordered all the specialty tools and parts needed for this job…a torque angle wrench and OEM timing belt tool, the gasket set, new head bolts, new radiator and radiator hoses, new thermostat and housing, new heater hose and metal coupling. So far, about $600 in tools and parts.
The only thing I haven’t decided is if it makes sense to buy a remanufactured head for about $400 online, or to have the existing one cleaned and resurfaced for about $150, or fully reconditioned for about $400. I want to keep this car on the road for as many years as possible, since it’s a real hassle to buy a used car.
This is what I have always been told. Do a valve job on an old engine and expect higher oil usage. Then other guys have told me never open up a high mileage engine, but we were talking in the several hundred thousand mile range. Horse left the barn now though.
Seriously ? I don’t buy used vehicles but if I had to I could find and purchase something in less then a week . If I saw something on the web that I like in the morning I could test drive and make a deal that afternoon.
