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how about this one, it just makes my head hurt.?
on a 83 ford bronco, a co worker was getting it ready for smog. was trying to get timing checked and adjusted to spec but the first guy that checked it said that it was off by 97 degrees! the owner of the truck came back to me and repeated this to me, i told him that if this were true, the engine would not run. the second shop that he went to adjusted timing to where it should be and now idle speed is low and the engine runs hot. what are your thoughts on this.
it has not made it in for smog yet, and i do not know if it will pass with the running conditions. the engine overheats in a short period of time.
as i said before timing according to the harmonic ballancer is dead on during this period.
to continue on, timing has to be set within a window, like 14 degrees btdc +- 5 as an example. at this point i am curious if the harmonic balancer is not part of the problem. if the inner ring or outer ring has slipped on the rubber isolator, that could explain it. but i did take a look at that and it dos not look like that has happened, and a replacement new is 140.00 so we do not want to throw parts at the problem until it goes away.
timing is checked as part of the smog inspection. if it is off, emissions will be higher than allowed.
timing is checked as part of the smog inspection. if it is off, emissions will be higher than allowed. and no it did not pass because the truck will not maintain the 25 mph on the dyno. i am unsure if it is related or a dumb driver at that point.
it is the original ballancer, so it cannot be the wrong one, although the timing ring could have slipped. as i said before timing was set to spec according to a timing light, it really does not matter of the distributor is a tooth off or 500 teeth off, timing is still set up by the distributor.
15 個解答
- 1 十年前
What are the circumstances leading up to the necessity of checking the timing? Find a manual, library, local auto parts store, internet etc...... 1- locate #1- cylinder, remove plug wire and plug. Use a small piece of wood, similar to a chop stick, stick it in the cylinder. Some times it is helpful to have a friend hold the stick so it doesn't bind between the head and the piston. Turn the engine over by hand at the harmonic balancer (preferred) or bump the starter a little at a time. When the stick is stick out all the way this is TDC. #2- Remove distributor cap, and look for a mark inside the distributor or the cap. Check your harmonic balancer and see if the timing marks line up. If they don't, #3- rotate engine another 360 degrees. When at TDC and the timing marks are lined-up, the rotor inside the distributor should be within 5 degrees or so of the #1 position of the distributor. If the truck is over heating, your timing is too advanced. #3- loosen distributor hold down clamp and rotate the distributor according to the manual to set the timing. #4- Check and make sure the harmonic balancer has only 1 set of timing marks on it. If this doesn't cure problem, I would have to know the circumstances leading up to why you checked the timing to begin with.
Before having your emisions checked, put a piece of cardboard in front of your radiator so the engine runs hotter. Use premium gas as well.
GOOD LUCK!
- ClassicMustangLv 71 十年前
set if back so it runs right, then take it to a pass or don't pay, if it fail because of the timing you may have to get a new crank pulley or get the old one re-indexed..
I think those have a distributor sprout that has to be pulled before you time it..
ADDED:
If it won't run at normal settings, but will run half *** at what you say,97 degrees off, then the timing chain has probably jumped a tooth or two.. One way to check is by compression test, all cylinders will be down, maybe at 100 or even below that.
資料來源： my experiences - 1 十年前
it sounds to me that they over advanced the timing, and when an engine idles really slow the coefficient of friction between the piston rings and the cylinder walls increases causing more heat to go along with the increased heat of over advanced timing. At low speed the oil pump doesnt generate very much pressure only compounding the issue. This is why it is running hot. as for the timing, I suggest bringing the engine to top dead center on the compression stroke, turn the distributor housing until the rotor lines up with the number one plug wire and start it up. make sure to either scribe the timing marks with a sharp pick or use a light paint on them to make the marks more visible, and set the timing from there.
- Scott MLv 61 十年前
Did it pass smog? If yes, then change the timing to where you believe it needs to be. If not, take it to yet another shop. Find a shop that knows OLD cars, not the new ones.
Those testers are drones that run the smog machine and follows what is says. I'm surprised they even know what a distributor is. Owners can't affort do have their best techs working a SMOG tester.
- 1 十年前
Sounds like they over advanced it. How does it start up and shut down? It most certainly won't pass smog test. It has to hold idle spec'd in the manual. Doesn't hurt (much) to get a third opinion! Preferably someone ASE certifiable. Not just certifiable!
- suzonkaLv 41 十年前
being that the engine is old, I would just turn the distributor while its running and listen for it to pick up speed then back off ,turn the distibutor the opposite way about 1/4 turn ,lock it down with the bolt and road test it.
資料來源： self tauight and books - 匿名1 十年前
Instead of using printed specs try using the #s that work.
If it's off by 20 degrees, runs cooler and passes emissions who cares if it is off the mark, But make a note of the #s.
- 1 十年前
In some states cars older than 25 years old do not have to pass smog. Have you checked your state requirements?
資料來源： dmv.org - m cLv 41 十年前
it sound like the car is still off on the timing, if it is even off 1 tooth, like what happen when my husband rebuilt my car, it ran hotter than normal, and it was hard to start ,and was jumpy. moving one tooth forward, my car does not over heat, and runs so much better......................
- 1 十年前
Timming still off.Too fast back it off alittle not much and see how it does.
資料來源： Been there done that. FORD
