|
| | |
|
|
fuzzy1
User
Jan 25, 2008, 7:35 PM
Post #1 of 8
(6384 views)
|
|
Washed Cylinders??
|
Sign In
|
|
Here is another one for you to ponder.
I have a 1986 ford F150 5.0L in the shop. Customer had been complaining that he was experiencing a signifigant power loss over a 2week peiod.
I drove vehicle and yes it had a major power loss. I pulled vehicle into shop and it died and would not hit again. NO start at all. I checked fuel pressure(normal).
Checked valve timing (ok there). replaced Plugs. Checked air filter(clean).
pulled valve cover to check for cam movement (ok there). Compression test showed 3cylinders at 65 psi, 1 cyl at 35 and the rest avg at 55 psi.
I assumed then that the cat was plugged so I cut pipes in front of cat and still no start.
I assumed cylinders were then washed due to flooding caused by plugged cat. Filled cylindes with trans fluid and soaked over night. Next morning blew out oil installed new plugs and after about 3 minutes of cranking engine, I finally could hear the compression come up and engine started.
Test drove vehicle 3miles and parked it. let is sit for about 30 seconds and and tried to restart and all i got again was a free spin with a lack of compression. Let sit for 1 minute and cranked again and engine built compression and then started. I let customer drive vehicle and when he returned he repeated a shut down and restart sequence 3 times. Engine started everytime.
Now we let the vehicle sit for 4 hours and tried to restart and yes it did start with no problem at all, So my question is why would it have lost compression a second time after the initial test drive? vehicle is now going to sit outside and see how is starts in the morning. Im expecting it to fire up but still would like to know why the second loss of compression.
Thanks for your info,
Fuzzy1
|
|
| |
|
|
Tom Greenleaf
Ultimate Carjunky
/ Moderator
Jan 26, 2008, 2:39 AM
Post #2 of 8
(6377 views)
|
|
Re: Washed Cylinders??
|
Sign In
|
|
Guess: The timing chain is jumping around!!
T
|
|
| |
|
|
fuzzy1
User
Jan 26, 2008, 6:13 AM
Post #3 of 8
(6372 views)
|
|
Re: Washed Cylinders??
|
Sign In
|
|
would I have not seen this this when i checked the timing? I mean would the timing mark on the crank pulley have been jumping back and forth while it was idling. Let me also mention that the engine in it is only about 4years old. I know anything is possible but on such a new engine i kinda doubt its the timing chain.
I will go back and check chain lash by rocking crank and watching ign rotor.
I will post back with any new findings.
Thanks,
Fuzzy1
|
|
| |
|
|
Tom Greenleaf
Ultimate Carjunky
/ Moderator
Jan 26, 2008, 6:56 AM
Post #4 of 8
(6370 views)
|
|
Re: Washed Cylinders?? Ford 5.0 V8
|
Sign In
|
|
The guess was because the noted compression was too low to run an engine yet it could run?? So WTF - right? (F=Fun)
In my collection of oddities that is one of them now twice! Had one 21 years old from all history known from new (Olds) and it would pull that just for one second - no run - then be fine for a YEAR! I knew what it was and was too lazy to replace it and sucker finally did make me walk. When I got in there the orig chain was evenly worn down (plastic gear) no teeth missing and I could remove the chain without taking off the sprockets - defies chances but it was mine and happened.
Other oddities: Pin on dist gear loses its position and gives whacked symptoms. Just one of those.
----- Late 80s 5.0 Ford Truck - a month of frustration! Had spark at wires and on time, compression, fuel proper and compression and no start or even pop?? (plugs were soaked from trying but visually dry when checked) New plugs after torch drying old ones didn't work, no start and this time cranked fast like no compression?? Compression was off on all but when it died just stopping at a store from being fine doesn't make sense?? It was the chain jumping.
Old history: Camshaft cracked but would still turn as the split was at an angle and it could still turn.
Those are really OUT THERE for possibilities, very rare but I've witnessed or been involved with those and the subsequent hair loss
These probably would show up with rocking the crank while watching the dist rotor.
Please hit back with what you find for archives....
T
Note: Plugs under compression that are in or have been fuel soaked (oil soaked?) themselves or the surrounding engine's combustion chamber) can find ground without making a spark - chamber can do it with new plugs - witnessed!
|
|
| |
|
|
fuzzy1
User
Jan 26, 2008, 6:43 PM
Post #5 of 8
(6362 views)
|
|
Re: Washed Cylinders?? Ford 5.0 V8
|
Sign In
|
|
Yes i would agree those are some real oddities.
So for an update on the ford in question here is how it's day went. The customer picked it up today to have the exhaust system repaired where we cut the cat loose. When he started it up this morning it started right up and ran for about 30 seconds and died. It went back to a free spin for about 30 seconds then hit compression again and sounded like a dragging starter. We let it sit for a few seconds and hit the key again and it fired up no problem. After a very short warm up I and the owner heard a very distinct knock and the engine idle fluttered then a few seconds later a second knock was heard and the engine died, again leaving it to a free spin condition to compression to a normal start. Once restarted it did the same exact thing again, knock= idle flutter knock=die and so on. Once you keep the engine running it does fine until idle and the second knock happens and then dies.
This series of events does lead me to think your right in the timing chain jumping. Will do tear down tomorrow. As far as manualy checking chain slop, i set crank to zero pulled dist cap off and turned crank. crank rotated 10 degrees before rotor moved. I will know more for sure later tomorrow and will repost results.
Fuzzy1
|
|
| |
|
|
Tom Greenleaf
Ultimate Carjunky
/ Moderator
Jan 27, 2008, 4:00 AM
Post #6 of 8
(6359 views)
|
|
Re: Washed Cylinders?? Ford 5.0 V8
|
Sign In
|
|
10 degrees is at least 5 more than I would like to hear! Bingo!
What amazes me is that the chain can jump a tooth or two and somehow jump BACK!! I would think the next jump would be another couple teeth the wrong way which would show up so much more easily but I've seen it happen as said??
Keep us posted - this is interesting,
T
|
|
| |
|
|
fuzzy1
User
Jan 28, 2008, 7:29 PM
Post #7 of 8
(6348 views)
|
|
Re: Washed Cylinders?? Ford 5.0 V8
|
Sign In
|
|
 Ok Final chapter in this book,
It was in fact the timing chain. Once tore down to chain and gears i was able to remove chain off of cam and crank gear without removing the gears. Its all buttoned up and running like a top again with the exception of a small coolant leak at the t-stat housing, i'll tackle that tomorrow.
Hats off to those who supplied the information leading me to the cause, much appreciated.
Fuzzy1
|
|
| |
|
|
Tom Greenleaf
Ultimate Carjunky
/ Moderator
Jan 29, 2008, 1:48 AM
Post #8 of 8
(6345 views)
|
|
Re: Washed Cylinders?? Ford 5.0 V8
|
Sign In
|
|
 Hot dang! Way to go and thanks for posting findings.
T-stat tricks: Wire wheel threads on bolts so they work with fingers. Use 1/2" timing wrench on the tricky bolt.
T-stat can easily fall down un-noticed. Glue, wire (removable) or do anything that prevents it from falling. The origs had barbs to hold them in place and are unavailable that way now - trust me I know! Just taking an orig out destroyed it so you won't find one...........
T
|
|
| |
|
Auto Repair Home
SEARCH
WHO'S 
LOG 
Strut spring orientation and strut mount tension nut
Please Help - Knock sound & engine fail
Brake Seals Bulging
