Help with a 2.8
#1
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Help with a 2.8
Hey everyone! I'm new and I'm hoping for some advice. I have been on the forms reading for months now but I just now have the courage to join and discuss.
I have a 2.8 that had an intake manifold leak. I should have cut the gaskets I think but I didn't.
The manual I had was wrong with regard to the lifters and pushrods for zero lash and then tigthening past. I went the 1.5 turns past 0 lash and there was NO compression.
I researched on here for days, for weeks, and tried many things.
I ended up doing 0 lash + .05 turns. Engine ran great but sounded like a diesel.
I tightened them up another half and it still sounded like a diesel, half past that and the valves weren't fully closing so I backed off back to 0 lash + .05
OK, so compression was great, the car ran great, it was just loud....
I ordered a new intake gasket, new push rods, and new lifters....
I installed all of these....
set to 0 + 1.5 and no knocking, great compression
but..... intake gasket failed.
took it apart, warrantied the gasket, still failed.
Noticed that the fel pro gasket was kind of wonky. the first one I had (sounded like a diesel) was a slightly different material and better cut. It didn't work.
I decided what the heck, I cut it the next time and used the copper gasket spray to hold each section perfectly in place, it leaked.
the heads are smooth with a straight metal edge. thought about that. Compression is good, thought about that.
Got another intake manifold, put it on... still leaks.
I'm stumped.
I took it apart opposite tightening. I tightened in two steps per the book.
I even got bolts with the manifold in case they were stretched.
we're back apart but I'm not confident that I will do any better this time than I have every other time on getting it to seal...
any advice is appreciated. Please!!
I have a 2.8 that had an intake manifold leak. I should have cut the gaskets I think but I didn't.
The manual I had was wrong with regard to the lifters and pushrods for zero lash and then tigthening past. I went the 1.5 turns past 0 lash and there was NO compression.
I researched on here for days, for weeks, and tried many things.
I ended up doing 0 lash + .05 turns. Engine ran great but sounded like a diesel.
I tightened them up another half and it still sounded like a diesel, half past that and the valves weren't fully closing so I backed off back to 0 lash + .05
OK, so compression was great, the car ran great, it was just loud....
I ordered a new intake gasket, new push rods, and new lifters....
I installed all of these....
set to 0 + 1.5 and no knocking, great compression
but..... intake gasket failed.
took it apart, warrantied the gasket, still failed.
Noticed that the fel pro gasket was kind of wonky. the first one I had (sounded like a diesel) was a slightly different material and better cut. It didn't work.
I decided what the heck, I cut it the next time and used the copper gasket spray to hold each section perfectly in place, it leaked.
the heads are smooth with a straight metal edge. thought about that. Compression is good, thought about that.
Got another intake manifold, put it on... still leaks.
I'm stumped.
I took it apart opposite tightening. I tightened in two steps per the book.
I even got bolts with the manifold in case they were stretched.
we're back apart but I'm not confident that I will do any better this time than I have every other time on getting it to seal...
any advice is appreciated. Please!!
#3
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Re: Help with a 2.8
the original leak was from the china walls. the rtv had failed there.
valve noise was the sounding like a diesel part. that's over now. new lifters took care of it.
the issue now isn't the china walls - i knew to RTV them.
It's leaking coolant into the oil and the cylinders.
valve noise was the sounding like a diesel part. that's over now. new lifters took care of it.
the issue now isn't the china walls - i knew to RTV them.
It's leaking coolant into the oil and the cylinders.
#5
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Re: Help with a 2.8
it shouldn't be a head gasket failure. It ran perfectly until the intake was pulled and this started directly after the intake was replaced. Nothing started until the intake was pulled to fix the leak at the china walls. It's clear when pulling the intake that coolant is leaking at the channel near cylinder 1 and coming into the oil via the valley. you can see on the gasket where it has been passing it.
#6
Re: Help with a 2.8
FelPro gaskets rarely fail when torqued to spec in the many years I have used them. Might a good idea to test for leaks on the intake manifold with smoke machine or similar homemade unit. Try spraying the intake gasket area with carb cleaner while the engine is running and listen for change in idle on the manifold before. When spraying have a fire extinguisher handy.
Before assuming the intake or head gaskets need replacement. Run a compression test and see what PSI is for each cylinder. With the engine running look for white smoke from the tailpipe. Check the oil and look for milky fluid. When the engine is hot pull the dipstick and put a small amount on the exhaust manifold. Oil on a hot exhaust will coolant will crackle or sizzle like bacon. Oil and fuel could be mixing into the system. If that happens, then you’ll have a milky-colored mix when you check the radiator. If you have access to a radiator pressure tester pressurize the system and look for drop in pressure indicating a leak.
Before assuming the intake or head gaskets need replacement. Run a compression test and see what PSI is for each cylinder. With the engine running look for white smoke from the tailpipe. Check the oil and look for milky fluid. When the engine is hot pull the dipstick and put a small amount on the exhaust manifold. Oil on a hot exhaust will coolant will crackle or sizzle like bacon. Oil and fuel could be mixing into the system. If that happens, then you’ll have a milky-colored mix when you check the radiator. If you have access to a radiator pressure tester pressurize the system and look for drop in pressure indicating a leak.
#7
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Re: Help with a 2.8
Hi Mark, thanks for the reply. I have actually used a different intake manifold now and we're still not sealing. 175-185 on compression. Each time, the cylinders that fill changes. They're between 1-3-5. I can tell it has changed each time because I take the plugs out and crank it after I see the coolant coming out of the tailpipe and it's varied each time between coolant only on 3, coolant on 5, and oil and coolant on 1. I've had it apart a number of times. Mind you, it ran beautifully with no issue until it was taken apart. The changing cylinders make me think that it's not the heads. I just replaced my torque wrench with a mac digital... bought a new gasket yesterday.. No change. Coolant in the oil and out the tailpipe, moved to cylinder 1 this time as for where the fluid is filling the cylinders. Ran it until it was hot (white smoke but no knocking. Tested the cooling system for exhaust gasses (head gasket leak test) and none were detected. I'm totally lost. 13 the first go around, 19 the next. outer rear, outer front left, opposing the outer right, inward left again same path, inner right for the torque and then rear nut and front nut in the center. Nothing is leaking onto the exhaust, nothing is leaking externally., the coolant is running into the intake ports and down into the valley to get into the oil. I just cant figure out what I'm missing or doing wrong here.
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#8
Re: Help with a 2.8
Could the coolant be coming in through the throotle body? There are 2 small right angle coolant hoses that sometimes leak in the front of the engine. You might try bypassing these temporarily and see if the problem goes way.
#9
Senior Member
Re: Help with a 2.8
Did you RTV the intake gasket surfaces around all water jacket points?
Been a while since I did this on a 2.8 but i think you have one the end of each head for a total of four places coolant from the heads comes in contact with intake gasket material.
Been a while since I did this on a 2.8 but i think you have one the end of each head for a total of four places coolant from the heads comes in contact with intake gasket material.
#10
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Re: Help with a 2.8
Hey guys....
I had the heads checked and reinstalled them.
OEM intake gasket
RTV on the 4 gasket to channel mating surfaces
Still sending coolant out the tailpipe
-BUT-
By accident, I learned something....
When i squeeze the upper radiator hose, coolant is shooting out of the brake booster metal tube. I forgot to hook up the hose.
I bet this was happening before and here's why.. when I squeezed before, with it hot, steam was coming up the TBI. I thought it was because the gasket wasn't sealing, then on the second gasket I thought it was the intake so i got another entire intake... now it's still doing it. Any ideas? .
I had the heads checked and reinstalled them.
OEM intake gasket
RTV on the 4 gasket to channel mating surfaces
Still sending coolant out the tailpipe
-BUT-
By accident, I learned something....
When i squeeze the upper radiator hose, coolant is shooting out of the brake booster metal tube. I forgot to hook up the hose.
I bet this was happening before and here's why.. when I squeezed before, with it hot, steam was coming up the TBI. I thought it was because the gasket wasn't sealing, then on the second gasket I thought it was the intake so i got another entire intake... now it's still doing it. Any ideas? .
#11
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Re: Help with a 2.8
Hey Guys!! Thanks for all of the help and advice, I really appreciate it.. Now, please let me tell you what happened. It's nuts but I didn't know.
I disassembled the car and did the gasket, you know that. The lifters were crushed, you know that. I took it apart again and all hades broke loose... you know that.
Here's where it went wrong. The kid and I were cleaning, painting, and moving parts around. He didn't like the dull faded brass look of the connector for the booster so he decided to go and get a knew one... can you see where this is going yet?
The problem was that he mated the fitting not with the booster line but with the water line... so it all went together... wrong.
and the treads were just tight enough that the booster went into the water jacket and was able to torque down - just.
so all of this time... yup... don't I feel dumb.
But it's fixed.
I disassembled the car and did the gasket, you know that. The lifters were crushed, you know that. I took it apart again and all hades broke loose... you know that.
Here's where it went wrong. The kid and I were cleaning, painting, and moving parts around. He didn't like the dull faded brass look of the connector for the booster so he decided to go and get a knew one... can you see where this is going yet?
The problem was that he mated the fitting not with the booster line but with the water line... so it all went together... wrong.
and the treads were just tight enough that the booster went into the water jacket and was able to torque down - just.
so all of this time... yup... don't I feel dumb.
But it's fixed.
#12
Re: Help with a 2.8
Good to hear you resolved the coolant issue. Changing the oil at least twice to get any coolant out of places in the engine it does not belong would be a good idea. You also now have a spare intake just in case it is ever needed.
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