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XF EDDIE

86 XF Falcon Ute not starting

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Update: I installed the new intake gasket and unsurprisingly no change. Id like to believe that its running better now but it still appears to be down a cylinder. Im gonna pull the rocker cover and see if the valves are doing anything but i doubt that this is the problem. It doesn't make any sense to me with it having good compression and spark. Only thing i can think of would be a wiped or blocked exhaust valve. Any ideas?

 

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Valve not opening, due to wiped cam lobe, or collapsed lifter.

 

Do a no-fuel crank, and listen to the note -

is the tone even across 6 cyl's or does it vary in pitch, indicating a problem cylinder?

 

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1 hour ago, SPArKy_Dave said:

Valve not opening, due to wiped cam lobe, or collapsed lifter.

 

Do a no-fuel crank, and listen to the note -

is the tone even across 6 cyl's or does it vary in pitch, indicating a problem cylinder?

 

Can I get the same result by doing a no spark crank?

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3 minutes ago, XF EDDIE said:

Can I get the same result by doing a no spark crank?

Sparkydave means, use the starter trigger wire with the key in off position. crank it over and hear if the engine goes waaa waaa waaa waaa weeeerrr waaaa  every revolution, a different note on one cylinder. 

 

the fact it has even compression, suggests it should be fine. 

 

if it's been sitting ages (blocked exhaust etc) then it might be a valve sticking or lifter issue here and there. i'd still be inclined to run it more and see if it sorts it self out. 

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4 minutes ago, deankxf said:

Sparkydave means, use the starter trigger wire with the key in off position. crank it over and hear if the engine goes waaa waaa waaa waaa weeeerrr waaaa  every revolution, a different note on one cylinder. 

 

the fact it has even compression, suggests it should be fine. 

 

if it's been sitting ages (blocked exhaust etc) then it might be a valve sticking or lifter issue here and there. i'd still be inclined to run it more and see if it sorts it self out. 

Just went out and cranked it over. She sounds smooth with no funny spots. It does the same thing with or without the exhaust attached though I can try hollowing out the cat. Ive been driving it daily for about a week and a half like this and ive no change. If it was a cam/lifter/pushrod issue woild it affect compression?

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7 minutes ago, XF EDDIE said:

 If it was a cam/lifter/pushrod issue woild it affect compression?

 

You'd record slightly higher compression, on the cylinder with an exhaust valve stuck closed.

Compression would appear fine, to the untrained eye.

 

Look for compression that's a bit TOO good, in comparison to the others.

 

 

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Just now, SPArKy_Dave said:

 

You'd record slightly higher compression, on the cylinder with an exhaust valve stuck closed.

Compression would appear fine, to the untrained eye.

 

Look for compression that's a bit TOO good, in comparison to the others.

 

 

Ill rerun the test tomorrow and post the results

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@SPArKy_Dave I reran the test and it got funky. I had 150 on all except cylinder 1 which was at 110. However this is where it gets funky. I poured some atf down the cylender and when i tested it it fucked my schrader valve. however after replacing it I cranked the engine to clear the atf and whatdya know its back at 150. I only got one reading before my compression tester finally gave up the ghost but now it has me hoping it was a stuck ring. I'm gonna leave it to sit for 2 hrs before clearing it and taking it for a drive and ill update you then.

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Well I just got back from taking it for a spin and its terrible. Putting the headlights on is now enough to stall it. I would rerun the compression test but my tester gave up the ghost. At first it ran great but as it warmed up its now just fucked. A this point im suspecting a fucked up lifter not holding when the oil thins out or a wiped cam. I hope its not the cam for this engines sake otherwise its getting a clevo. Real shame for such a low kms engine to be shitty like this.

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Could be a bent push-rod also, however you'd usually hear the random ticking.

 

I'd pull the rocker cover, and idle the engine with the cover off.

Watch for anything obviously wrong.

 

If you know how, I'd use a dial micrometer to measure valve lift on all 12 valves,

look for differences in the recorded values.

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17 hours ago, SPArKy_Dave said:

Could be a bent push-rod also, however you'd usually hear the random ticking.

 

I'd pull the rocker cover, and idle the engine with the cover off.

Watch for anything obviously wrong.

 

If you know how, I'd use a dial micrometer to measure valve lift on all 12 valves,

look for differences in the recorded values.

Ive got a new rocker cover gasket so ill pull it off and give it a look. Just wondering would the atf burning off would have clogged up the cat?

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8 hours ago, XF EDDIE said:

Just wondering would the atf burning off would have clogged up the cat?

 

That's unlikely, IMO.

Keep us posted with what u discover!

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Well there's been a development. I haven't pulled the cover yet but I took her for a good drive today wide open going 140 and she ran perfect and when I pulled up it idled good but after giving it a rev it slowly lost cylinder 1 again. I noticed the misfire disappears after about 2000 rpm so I'm starting to suspect something lifter. Also it no longer stalls out when I come to a stop so it must have cleared out the atf. Still not to sure about the cat as the exhaust was clogged up with carbon to begin with as it was used as a farm runner at the end of its life. Any way to check or do I just have to hollow it out to see?

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Also I forgot to mention that it seems to not put out much exhaust out the tailpipe (even at 2000) you can barely feel it) compared to my f100 with the same engine although I can't tell if this is because of a blockage or the leaks in the system

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6 minutes ago, XF EDDIE said:

as the exhaust was clogged up with carbon to begin with

 

sure it wasn't blocked with a rats nest or similar? or rust

Just now, XF EDDIE said:

Also I forgot to mention that it seems to not put out much exhaust out the tailpipe (even at 2000) you can barely feel it) compared to my f100 with the same engine although I can't tell if this is because of a blockage or the leaks in the system

 

with the cat, when mine was blocked it was SO HOT, it melted the carpet 

if you can feel heat 30cm from it,  it's likely blocked. 

2000rpm you'd definitely be making a LOT OF NOISE and air flow, so i'd be leaning towards it being blocked by the description. 

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23 hours ago, deankxf said:

 

sure it wasn't blocked with a rats nest or similar? or rust

 

with the cat, when mine was blocked it was SO HOT, it melted the carpet 

if you can feel heat 30cm from it,  it's likely blocked. 

2000rpm you'd definitely be making a LOT OF NOISE and air flow, so i'd be leaning towards it being blocked by the description. 

I just checked the cat with a heat gun and the temps were pretty inconsistent some areas were hotter than others with the lowest being about 200 and the highest being almost 300 the average temp was about 220 but there were hot spots. Also when the engine idle got really rough it was making a horrible rattling noise from underneath. I cant tell if its the cat but it does sound like something from that area

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26 minutes ago, XF EDDIE said:

I just checked the cat with a heat gun and the temps were pretty inconsistent some areas were hotter than others with the lowest being about 200 and the highest being almost 300 the average temp was about 220 but there were hot spots. Also when the engine idle got really rough it was making a horrible rattling noise from underneath. I cant tell if its the cat but it does sound like something from that area

i reckon it will be the cat, broken. it's like a light weight rock, it can get blown into a blockage and then when low air speed (idle) just fall back enough to rattle around. (that's what one of mine in particular was like when i bought the car) 

 

there's other things that can rattle when there's issues, and one of the most unusual ones was a FLEXPLATE with rivetted  on ring gear and the rivets were loose/flogged out 

s-l1600.jpg

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I tried to hollow out the cat but it was so tough that even a socket extension barely broke it so I gave up however I drove it hard again and like before it ran perfectly for about a minute before going back to the way it was before. What could this be lifter? Head gasket? It's got me puzzled

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11 hours ago, XF EDDIE said:

however I drove it hard again and like before it ran perfectly for about a minute before going back to the way it was before. What could this be lifter? Head gasket? It's got me puzzled

head gasket will be constant, 

lifter won't affect it much in my opinion (i've had wiped ones, and they go ok on 5cyls)

 

blocked exhaust (cat) is still plauisble. find another? see if you can get an exhaust joint to make a "leaded" engine pipe replacement for it (tell em you've fitted the unleaded exhaust off your other car for example, or even you want it for testing/faults) (i'd expect $150 odd ?) 

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21 hours ago, deankxf said:

head gasket will be constant, 

lifter won't affect it much in my opinion (i've had wiped ones, and they go ok on 5cyls)

 

blocked exhaust (cat) is still plauisble. find another? see if you can get an exhaust joint to make a "leaded" engine pipe replacement for it (tell em you've fitted the unleaded exhaust off your other car for example, or even you want it for testing/faults) (i'd expect $150 odd ?) 

I might just try it with open manifold and see if that fixes it. Ill report back with what happens.

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4 hours ago, XF EDDIE said:

I might just try it with open manifold and see if that fixes it. Ill report back with what happens.


should film it from far away, will be some mighty noises and flames if you unbolt it from the head and run it. 
 

 

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1 hour ago, deankxf said:


should film it from far away, will be some mighty noises and flames if you unbolt it from the head and run it. 

I was only gonna unhook it from the manifold itself. I hope it fixes this turd

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a

1 minute ago, XF EDDIE said:

I was only gonna unhook it from the manifold itself. I hope it fixes this turd

ah yes, forgot about that, all good, just as much noise and flames, make sure there's no flameable fuel leaks etc around etc

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