Sick T-bird

Discussion in '4X4 Truck Talk and Repairs' started by Salthart, Dec 26, 2009.

  1. Salthart

    Salthart New Member

    North Carolina
    I own 3 Nissan trucks and 1 GMC. I own a Thunderbird and a Pontiac.

    I don't own the Nissans because I think they are the best trucks in the world. But because I have pulled the engine out of one so many times I could almost do it in my sleep. I know them..

    But this Thunderbird, Although its not a truck, I hope I can find a little help on it.

    Its a 93 T-bird with a 5.0 HO. And its dead on every cylinder on the drivers side bank.

    Compression runs low on all 4 of those cylinders. And the intake (Fuel Injected ) is stopped up where the PCV valve plugs up.

    The computer is fireing the injectors and the plugs are all firing.

    I removed the intake plenum and can't see that it is or the intake is stopped up there.

    The engine does not knock but there does seem to be a good deal of blow-by..

    What would take out all the cylinders on a bank at once ? BTW, I bought this car in this condition.

    There seems to be about 4 or 5 quarts to much oil in it so the blow-by could be a result of that.

    I have tried and tried to come up with some idea but my mind starts to draw a blank past the valve train being down on that side.. Maybe it stopped oiling and wore out the lifters ? ( I'm told that this thing has both a roller cam and roller rockers )

    My wife fell in love with this thing at first glance. The body is great but it could use a new paint job and some work on the insides. Help me if you can. I will pull and build the engine if need be but I'd rather find what and why so I can make sure it don't happen again..

    Thanks in advance for any help.
    Last edited: Dec 26, 2009
  2. hdfatboy29

    hdfatboy29 New Member

    too much oil in the pan can create all that blow by but does the oil look milky?? like anti freeze in it?? could it have a bad head gasket?? and to a point it sounds like it got hot and warped the head making it lose all the compression?? since it,s only one head i,d almost bet gasket or warped head. i,d pull the head and see were you are there if it,s warped or bad gasket. i hope this helps you i,m sure you,ve thought of all this

  3. Salthart

    Salthart New Member

    North Carolina
    Thanks for your reply. I had given up all hope that anyone would.

    No there is no sign of water. No "Milky" oil and not milky glaze on the parts. Also the radiator is full of brand new looking antifreeze.

    Now that the weather is warming, I may get it torn down before long. Thanks again and I'll try and keep posted what I find once I get started.
  4. smokey869

    smokey869 New Member

    im not much of a ford guy, but does that engine have the overhead cams ? if its like the 4.0 litrethay can have one broken 1 timing chain and still run, i am not sure on that engine though, i would do a compression test before tearing it down though, you may have good compression and something else wrong, i had a gm car that a guy was getting fuel out of a farm tank and rust had plugged off 3 or 4 injectors on it, they were firing but no fuel to them, just do a little checking before tear down will save some possible headaches lol
  5. psychomekanik

    psychomekanik New Member

    The 5.0 is the old 302. You've got a head gasket/head problem. But after running it awhile, I'd think you'd have intermix. (water in the oil) The blow by is common. The pcv system is usually plugged up. Follow the pcv hose from valve cover to the intake. If the valve seated in a rubber grommet on the lower intake in the very back remove the valve, and the grommet. there should be a screen type filter in the lower intake. Use a 4-5 inch wood screw screw into the filter to get a good grip on it and yank it out using a pair of pliers. dont replace it. Just run without it.
    Last edited: Jan 19, 2010
  6. drpepper

    drpepper New Member

    Somebody may have confused themselfs to death on that one trying to fix it before....
    I'm kinda really doubting a head and/or gasket right now to be honest.

    ... consider that you might not have any compression on that side because unburned fuel has washed the cylinders... whith that in mind, you might start at square one for a minute and just check a few things for possibilities before ya condemn it to death.

    Considering someone has been screwing with it before you bought it.....

    First- make sure the plug wires are routed right... I've seen this a bazillion times, folks look at a 5.0 HO firing order for a standard 5.0 or vise versa...... They're not the same.

    Second- See if'n ya got GOOD spark... replacing plugs in a flooded/washed cylinder(s) without "drying" the Cylinder(s) out FIRST will instantly and completely ruin a new spark plug.... especially generic or champion... champion REALLY suck--- use motorcraft ;)

    Disconnect your fuel pump.

    Chexk your oil (smell it) if it smels like gas.... change it, along with the filter - or you'll be sorry.
    That extra oil you mentioned MIGHT just be gasoline... aside from the dangers- gas in the oil pan will wipe out rod and main bearings in a hurry.

    Next... see if you can restore some compression.

    Again fuel disabled.....

    pull the spark plugs (all 8 of 'em) and squirt a little oil in the cylinders with the low compression and then crank it back out.... do this maybe a few times (lay a rag down or something to keep oil from squirting everywhere and possibly starting a fire when the manifols get hot )

    Take another compression check... any better? if it is, but still not up to snuff, then- oil and crank a little more...... when you're done, crank as much oil out of the cylinders as possible and if you've got good compression then put 'er back together.

    I'll add this... make sure your FP isn't too high. or you'll wind-up in the same boat if that was the initial cause.... also, clean the sludge behind the plate on the throttle body really good.... and while you've already got the intake off, break-up and clean the carbon from EGR passage.... good luck.

    ps- enable the fuel pump again-lol.
  7. Salthart

    Salthart New Member

    North Carolina
    Wow ! All this time without a reply and now look ! Lots of good advice here. I am going to try and put it to use.

    THis thing will start in a heartbeat. It just runs like a dog. And with the over filled oil and the clogged PCV screen, Its been pumping oil through the line off the oil fill port back into the breather box. A pretty good stream of it at anything above an idle.

    Being it has started and ran so well for 4 cylinders, I never thought about the wires being crossed. You can unplug all four on the drivers side and it don't change 20 rpm one way or the other. But I will for sure check on it.

    Being that this thing is what it is, I have not bothered to remove the rocker cover from that bank and see the valve action.

    I will try and keep posted what I find and thanks again. I'm no longer near in the dark as I was.
  8. Trapper-steve

    Trapper-steve Well-Known Member

    Bicknell, IN
    You might want to drain the oil at least down to where it should be? :confused1::confused1: