[jvolz]

I have a 1988 Nissan Sentra with the 1.6L throttle body injected straight 4. I have rebuilt the motor, and have since come into contact with plenty of small things going wrong. About six months ago, the head gasket blew while I was driving it and I had the head machined to work right again. It has since always misfired the first couple rotations when I start it cold, which I assumed was because it was cold. Without warning it wouldn't start about a month ago and I replaced the coil and it started up perfectly. All of a sudden about a week ago the same symptom popped up and it won't start. Found some coolant in one of the cylinders so I pulled the head off. The head gasket is in perfect shape, but every cylinder has coolant inside, with 1 and 4 being the worst. Though I haven't seen any coolant in the oil, and the gasket is fine, I'm not sure what the cause of this issue is. When I pulled the head gasket off though, I noticed that quite a few of the holes for coolant ports had been blocked off. It looks as though it came like that from the factory, but I can't totally tell. Any ideas as to what might be going on?

 

[rogoman]

Perform a compression test on all cylinders. The specs are: standard - 192 psi, minimum - 164 psi, Maximum Variation Between Cylinders - 14 psi. If you've got some bad cylinders, follow up with a leak-down test to determine the cause.

 

[smj999smj]

Rogo.... How's he going to do a compression test when he pulled the head off of it, already?

Jvolz.... It's been a long time since I've even looked at an E-series in person (even though I have a B11 sitting in my front yard...slowly disappearing under years worth of pine needles). It's odd to have coolant in all of the cylinders. Can I assume you checked the deck of the cylinder head and the top of the block with a straight edge and feeler gauge? The only other thing I can think of is somehow coolant was getting into the intake manifold and getting sucked into each cylinder. I have run into a couple of porous intake manifolds on E-motors, but not in a case where it was leaking coolant. Ideally, it would have been a good idea to pressurize the cooling system before the head was removed to try and locate the leaks, but it's a little too late for that. Maybe a crack in the manifold between the intake coolant passage and an intake runner? But, I'm just guessing at this point!

 

[jvolz]

Rogo.... How's he going to do a compression test when he pulled the head off of it, already?

Jvolz.... It's been a long time since I've even looked at an E-series in person (even though I have a B11 sitting in my front yard...slowly disappearing under years worth of pine needles). It's odd to have coolant in all of the cylinders. Can I assume you checked the deck of the cylinder head and the top of the block with a straight edge and feeler gauge? The only other thing I can think of is somehow coolant was getting into the intake manifold and getting sucked into each cylinder. I have run into a couple of porous intake manifolds on E-motors, but not in a case where it was leaking coolant. Ideally, it would have been a good idea to pressurize the cooling system before the head was removed to try and locate the leaks, but it's a little too late for that. Maybe a crack in the manifold between the intake coolant passage and an intake runner? But, I'm just guessing at this point!

I’m curious though, when we pulled the head off, the head gasket that was on there was blocking a handful of the coolant ports from the head to the block. Is that normal or is that something that the gasket maker messed up??

 

[rogoman]

Rogo.... How's he going to do a compression test when he pulled the head off of it, already?

OH OH my bad. I guess I didn't read his post accurately. That's what happens when I'm up late into the night. But at least he's got some specs that may be useful for him.