Krog321

i changed the timing belt on my 1994 pickup 3.0 v6 Sr5 and before putting everything back together I spun the crank twice to make sure the marks came back to tdc and they did. Now when I started it there is a popping sound when idling. And it runs like ˟˟˟˟. I shut it off quickly but have no idea what could be wrong. I also changed the rotor and cap and put a new oil pump in. The pan gasket was also replaced. Can someone please give me an idea of where to start. Thanks

wyoming9

iTrader: (1)

Popping sound is very vague !!

It can mean so many different things .

I think of the sound of a 45acp

Is it a mechanical sound something hitting as it rotates ??

Does it increase as the rpm increases ??

A exhaust leak have any parts of the exhaust apart??

Spark plugs out ?? One still loose.

In your crawling around doing the work did something get bent

As this did not make the noise before it was something you did .

Vacuum hose off or installed wrong .

Krog321

Sounds like if you were spinning a towel in your hand and it hitting something every time it went around. I didn't rev the motor because I didn't want to damage anything. No exhaust came apart. But sounds like a loud exhaust leak. Plugs never came out. It was very hard to start but finally did fire.. I have never heard anything like it so it's hard to describe. Sorry

warpigg

Check your ignition timing it sounds to me like you have it 180 degrees out. Need your motor at a couple degrees before tdc. Don't turn the engine backwards if you miss it. Then you want your distributer right before the number one spark plug wire. If it's alittle after it can somehow still start sometimes but it will run awful. Almost sounds like it's knocking it can be that bad.
​​​

Krog321

i sound the engine around to TDC and when I look at the rotor it is not facing the position for cylinder 1. So I am thinking I should pull the distributor and realign it. Is that ok to do?

warpigg

Yes sir. You want to make sure it's alittle bit before cylinder one so It properly starts the firing order

Krog321

I will update after i do this. The only way I am saying it is tdc is by the marks. I haven't seen what the valves are doing to be sure

warpigg

I'm not familiar with the v6's but as long as the crank and the two cams are lined up at tdc or alittle before and you didn't reverse the rotation at all it should work. After you start it you can rotate the distributer and that adjust timing. It will increase and or decrease idle depending on which way you turn it

Krog321

I sound the cams backwards to line them up to the marks but not the crank I can't see how spinning the cams should make a difference but maybe you have insight to this. This was done with the belt off. As I said before I did do the check by spinning the crank twice to make sure it came to TDC. On the cams and the crank after reinstalling the belt.

warpigg

Yeah you just don't want to turn the engine backwards at the crank with the belton. It can make the belt go slightly slack and can give you a misread on the timing marks. But if the belt wasent on it doesn't matter.

scope103

Careful. Don't forget that there are TWO TDCs for every turn of the distributor. If you think you might be 180° out, you'll need to remove the upper timing cover (easy to do) so you can see that the marks on the two cams are pointing up when the harmonic balancer says TDC.

Setting the distributor this way is very approximate; you will (of course) need a timing light to get it close.

Because the distributor drive gear is helical, it is quite easy to get it off by one tooth. Which is about 28°. If your timing light shows you off that far, recheck the insertion of the distributor.

warpigg

I've never used a timing light with my method and I've done it atleast ten times. Never had an issue

Krog321

That didn't work moving the distributor it doesnt even try to start now. I have no idea what to do.

warpigg

I'd say your cams are out of timing or you didn't put the distributer cap on the right plug wire. It's hard to say not being there or atleast seeing it. A pic of the cam and crank timing marks and the distributer with how the arm is oriented would help your cause. Because otherwise I don't know. Do you have the plug wires on the right way? Do you know the firing order?

Krog321

Yeah firing order is 1 2 3 4 5 6 I can get you the pictures but I did notice that when the pulley on the crank matches the 0 on the plastic lower timing cover the cams are off past the timing marks. Getting picture of the crank will mean I have to take it all back apart.

warpigg

If your timing marks are off then they need to be reset to where they should be. You may have damaged the engine from starting it with the cams out of phase.

Krog321

I question that because we spun it twice to make sure it came back to tdc on the crank pulley in relation to the cams.

Krog321

When I did that I never heard or felt any valves hitting cylinders it all went smooth

warpigg

You just stated how the timing marks are off... This won't fix itself unless you line all the timing marks back up and get the cams in the right phase

Krog321

I get that but when you line the crank up the lower timing cover can't be on so how are you supposed to line it up? There is a mark on the oil pump and a mark on the crank shaft pulley which I lined up. Maybe I am confused on how to line it up.