transam85dudeman

I gotta replace the timing chain, hopefully it will resolve my issue with the timing jumping. In the procedure... would I have to drop the pan? If I were to loosen the back and removed the front oil pan bolts...am I going to have gasket issues? If i were to raise the block, I would do it with a jack and wood under the oil pan and set it on 3-inch blocks above the mounts. If I have too, I might as well replace the oil pump, gasket, along with the mounts. Im gathering parts together and considering going with a true double roller timing chain. any issues with front crank case cover? sucks spending on oil when you got to drain it a week later. ehh, a good flush douchs. . Any suggestions. ???

Apeiron

What's your issue with the timing jumping?

transam85dudeman

(At the moment the starter solenoid is bad )

With the Tan wire (EST) disconnected and a fine white line on the harmonic Balancer groove and another on 6* on the marker. I checked the timing. I recently replaced the pickup coil, had the module tested and replaced the Radio condenser connected with Module. I had marked the rotor twice (one before removing the distributor and one after. I even double checked it with finding TDC on compression stroke #1. Replaced a wire because it was burnt. and double check the firing order. when I turned it over it ran (it didnt before). I disconnected the (EST wire) of coarse with the engine off and procceded to time it. While it was running I matched it up to 6* (easy part). after about 6 seconds it would jump to *10-13* BTDC for another 4-5 seconds and returned to 6 degrees, with slight acelleration on the throttle, it almost felt like the MAF was out. I had replaced the Mass airflow sensor back in Feburary so it couldnt be the issue (im working on getting a burn off relay). My guess is the cam is slacking back and forth, and while raising the RPMs it was giving me little_little backfire/vaccum related problems. the Distributor gear is Meshing properly and is hardly hardly no wear at all. I seperated the Plug wires and checked them. I had already replaced most sensors and ETC. As a procaution cause its been sitting for since last August, I want to dump the gas and seal the tank with gastank repair gunk{considering its 21years old}. It had occasionally been driven the Auto shops for a waste of freaking money to diagnose the issue) i took it to the this one shop for a diagnoses, they wanted $450 dollars and they didnt know crap! I knew more than the dudes...I told them basically to go F-themselves and brought up legal issues settled for 85 bucks. they told stupid made up crap, they were right about the MAF, but i knew that after spending time in the shop with workers I dont trust them.) But yeah pretty much I was looking for any reason why it is jumping. I checked out this website<<heres a quote from the web page,

" Telltale signs of worn out timing chains are:

Rough idle.
Sluggish performance and poor economy.
Sudden engine performance change including the inability to start the engine.
Intermittent backfire through the intake manifold.
***Inconsistent ignition timing or a clattering noise coming from the front of the engine."

Hopefully this helps.

Apeiron

Have you tried shimming the endplay down on the distributor?

transam85dudeman

Endplay? Like up and down or turning the crank with a wrench and check when the distributor starts turning? Im sorry. (FYI)I replaced the water pump because I assumed the bearings were out, and it was cause knocking sounds(not pinging from the cylinders) I could move the pulley on the pump up and down just a tad, which I felt was setting off the knock sensor. besides it needed it. But it didnt go away.

jr. gearhead

up and down motion of the shaft. you can check it w/o pulling the dist, just take off the cap and lift the rotor gently.

transam85dudeman

Actually when the distributor was out, I tilted it upside down and upright, the shaft moves a bit, If i wanted to i could shake it up and down, and it would knock back and forth. Are you saying this isnt normal, i wouldnt know. It was like that when i pulled it. I havnt got my hands on a brand new distributor yet but I take it, that the circular motion from the cam spinning the shaft that its quite possible it might swirl upwards. but I dont know. I was too cheap to replace the base of the distributor, I ended up just replacing the parts inside, I did that special layer of white Jizz on the under the module too.

Sonix

iTrader: (1)

it *should* have something like .015" play. People have upwards of .060" play, which is quite easy to feel.
You can get a set of shims, by mr gasket. "Distibutor shims", I think it's called.

Take out the dist, stick feeler gauges between the gear, and the shaft at the bottom of the dist. Remove the roll pin, add shims until you'll have ~.015" play *I THINK*, then put it back together. Spark scatter is the result of too much endplay, shimming it fixes it.
I think it's kinda a rare problem though...

Apeiron

It's somewhat normal, but not especially desirable. Every .010" of endplay gives you about 1 degree of variability in timing. You don't necessarily need a new distributor, you can shim the one you have until you've got about .010"-.020" or so of clearance.

It's not necessarily your whole problem, but it's a possibility and it's a whole lot easier to do than changing a timing set.

transam85dudeman

I had seen those shims in Jegs, i like where you guys are going. Im going to pickup a feelgauges, I told a friend i'd help him tune up his old bus valves/points. Ill check out the distributor too.
I was wondering about the oil pan and front case cover...whould i have to drop the front of the pan? or simply just remove the front case cover? Haynes say to drop the pan and to do that i gots to raise the engine on blocks? Ehh thanks for the help,.

Apeiron

You can't easily get the timing cover off without dropping the front of the pan.

TreeFiddy

An idea I just had - maybe dumb, never tried - pull out the plugs, rotate the crank until a valve has opened, then rock the crank cw/ccw 10-15 degrees - the valve should move exactly in sympathy - dial gauge might help. If not then the chain is stretched and rocking the crank is just taking up the chain slack. The slightest crank movement with a lifter on an opening/closing ramp should produce some visible/measureable valve movement I would expect.

I changed my timing set by loosening all the sump bolts just enough to drop it and slide the new cover/seal in - hoped that cracking the sump gasket in this way would not cause leaks - it didnt - guess I got lucky!

vorgath

Could anyone please describe what you guys mean by the timing jumping, i.e. how will the engine act ?

Reading this post, I'm wondering if that's what has been a tiny issue with my car, mostly at idle though.

bobdole369

Only way to tell is with a timing light vorgath.

By timing jumping they mean that the timing moves from the desired 6* BTDC to some other value. Essentially the timing chain skips a tooth and suddenly your at 18* BTDC or some value that doesn't allow the car to run. However I don't agree that this was sickdeaths problem - on my wifes 82 her timing set jumped a tooth and since the timing set doesn't rotate the other way, it didn't go back and forth. I don't see how a skipped tooth or a slack cam could go back to normal unless it goes back around again and then gets stuck back in the normal position.

Slipping timing chain isn't usually a tiny issue. You'd be backfiring all over the place, then suddenly it works right, then you wouldn't be able to start it, backfiring out the intake, etc.

transam85dudeman

Yeah man, the distributor's internal shaft up and down endplay is .060" Way too much. It should be .015" freeplay. I ordered MOROSO distributor shaft shims to take out the slack, along with a true double rolling timing chain from summit. I ordered a new harmonic balancer too. I had a lot of problems in that area. Im even debating putting a wooden block under the oil pan and jacking it up three inches to replace the motor mounts and oil gasket seal. Always if in doubt replace that distributor pin in the spider gear, it could affect it up to 3 degrees if loose.
-To sum it up, i realized i ought to replace the leaking powersteering pump, belts, hoses, fan motor and blades, new 108ampre alternator, and installing a permenent mini timing light w/tab. just "might as well while im here" parts. Neverhurts. I go Ac Delco for starter, but get get OEM parts from RockAuto.com....I got those shims from Jegs.com...and the harmonic balancer and chain w/gears from summitracing.com....Autozone sucks.