intermittent ticking sound from engine

[rstewart1737]

Hi all. I'm new here. Just bought a '99 Montana. Drove it home 160 miles and it ran great. Started it up later that day and there was a loud ticking sound like a noisy lifter. Next time I started it it was perfectly quiet, the ticking sound was gone. The thing sat in a lot for 15 months before anyone (me) bought it. So I'm wondering if the lifter is just sticking from dried crud that broke loose on the ride home. I plan on flushing the engine tomorrow and changing the oil and filter. Sound like a good plan? All other fluids were changed by the dealer.

-Rick Stewart

[rubberman]

i think that ticking sound is the manifolds. I read that somewhere in this forum.

[1999montana]

Hello Rick,

I noticed this too, but mostly first thing in the morning. The valve train on these engines is apparently not the quietest, but the noise does go away about 5 or 10 minutes after start-up. Ours became excessively noisy at one point.

At just over 100,000 KMs (64,000 miles) I replaced the serpentine belt. To my amazement, some of the noise I had been hearing went away and I was left with just the sound of the valve train. Click, click, tick, tick...well you know the sound. I wouldn't be too concerned.

Part of the sound you are hearing could also be 'piston slap' as I understand this is common as well. It goes away as the engine heats up and the pistons expand in the bores.

Bob

[eleveniron]

Originally Posted by 1999montana

Hello Rick,

I noticed this too, but mostly first thing in the morning. The valve train on these engines is apparently not the quietest, but the noise does go away about 5 or 10 minutes after start-up. Ours became excessively noisy at one point.

At just over 100,000 KMs (64,000 miles) I replaced the serpentine belt. To my amazement, some of the noise I had been hearing went away and I was left with just the sound of the valve train. Click, click, tick, tick...well you know the sound. I wouldn't be too concerned.

Part of the sound you are hearing could also be 'piston slap' as I understand this is common as well. It goes away as the engine heats up and the pistons expand in the bores.

Bob

Yes, the piston slap is very normal on these. When the piston holes are at the max diameter tolerance and the pins are at the minimum diameter tolerance. There is a GM service bulletin that covered this while the vehicle was still under waranty, but even then it is up to the service manager at the dealer you go to to decide if yours qualifies...mine did not and now at 202,000 kms it still sounds like it did when i bought it at 64,000 kms.

Steve

[rubberman]

btw, how easy was it to change the belt? I've done it before but not on a Montana and looks pretty crowded along the side.

[eleveniron]

Originally Posted by rubberman

btw, how easy was it to change the belt? I've done it before but not on a Montana and looks pretty crowded along the side.

real easy (looks worse than it is). Just use a wrench on the end of the tensioner assembly arm to take the tension off the belt. Once you slip the belt off of the tensioner pulley let the tensioner go. Remove the old belt, install the new one in the right routing, then use the wrench again to lift up on the tensioner and finish installing the belt around the tensioner pulley.

WARNING!!!! I just did mine again recently. When I was in there I noticed that the tensioner pulley was cutting into the side of the engine block. When the spring section of the tensioner assembly gets worn, the tensioner arm will sit off-set when the belt tension is on it and the pulley will rub into the block. There is only about a 1/4" clearence there with a new tensioner assembly. My block is OK but the groove is probably 1/16" deep and surprisingly very little damage to the plastic pulley. I now realize that there was a slight noise coming from that area of the engine, but it sounded more like a water pump starting to pack it in.

Steve

[rstewart1737]

Thanks for the replies. Today I ran Gunk engine cleaner through the engine for five minutes to disolve any kind of carbon buildup. I drained the oil and changed the filter. I added 4.5 quarts of Valvoline Semi Synthetic. Started her up and she's quiet as can be. I used semi-synth this time because if the oil clean and change trick didn't work, I was going to take it back and I didn't want to spring for full synthetic on a van that might have problems. But now since it seems to have quieted everything down so much, looks like I'll be using full synthetic next time. I took the family on a 100 mile trip today and there wasn't any evidence of any noise the whole time.

When I first heard this engine at the lot it was cold and there was a sort of a thunk thunk thunk sound coming from the lower end. The sales woman assured me that most of them do that and she started up several others to prove her point. They ALL did it... until they warmed up and then they quieted down.

There is still a little bit of noise from the top end of the engine but it's just the fuel injectors gently clicking away. Next thing on the agenda is a new belt.

Thanks all. I'm really relieved to know there's a Montana list out here.

-Rick Stewart
'85 Fiero GT with 5.0L Caddy V8/5 speed in progress
'99 Montana

[kpn]

My 2000 ticks on almost all cold starts. Its done it since we bought it new. Once warm it is quiet. I just attribute it to the piston slap or maybe a noisly lifter.

Keith