69ChBuLQ4

iTrader: (1)

I installed gm ls1 hot cam into my lq4 and replaced the stock valve springs with their ls6 springs. Didn't hear a clicking at first but there was a very light catch when I turn it over slowly. Eventually a clicking noise started happening I think twice during a complete rotation. I heard that clicking can start when there isn't oil getting to the hydraulic rollers. Either that or I really effed up and didn't degree the cam right. I lined the dots up when I swapped in the cam but now I'm wondering if I didn't do it just perfectly. Any ideas or comments on diagnosing and fixing this problem?

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I added some oil to the upper valvetrain and the noise got queiter today... I then checked the torque on the rocker arms and when I retorqued them the click came back louder in the problematic cylinder. This makes me think I didnt degree it right but idk.

Paul57

Maybe a bent pushrod??????
Was it a factory cam or aftermarket grind?

SOMbitch

iTrader: (8)

Go back over your rocker adjustment first and make sure one didn't back off.......

69ChBuLQ4

iTrader: (1)

I replaced the old pushrods with some new 7.4" (stock length) comp pushrods. Should just be a factory cam kit, got it from scoggin dickey and its a GMPP LS1 Hot Cam 219/228 duration @ .05...
Like maybe the rocker arm loosened up? Should I unbolt them and go back through the torquing procedure?

MPFD

iTrader: (5)

Does he have adjustable rockers?

Paul57

You should be able to just double check that they are still torqued. No need to loosen them up, in my opinion.

Paul57

Hopefully it was a new cam and not a regrind. If it was a regrind then the base circle was likely smaller than stock. I bought a new cam from a major cam supplier/manufacturer and found that it was a regrind...the base circle was considerably smaller than stock. Just trying to give you some ideas. How much did you turn the bolt after zero lash or did you just torque them down???

69ChBuLQ4

iTrader: (1)

So do the regrinds sometimes have lifter issues? i don't think the base circle was diff, not positive though
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I just torqued them to 22 ft lbs with the factory procedure. How many turns after zero lash tell you the rocker is sitting right with a proper pushrod length? i retorqued the ones where the noise was coming from to 24 when it made the noise louder. I am going out of town for a few days but ill check the torquing on the rockers when i get back on the 1st. I appreciate the suggestions

Paul57

Actually, I may have represented if mine was truly a re-grind. I am speculating that it was since the base circles were not the stock diameter...they were .070" and .080" diameter smaller than stock. This will translate to less lifter preload (.035" & .040" in my case) if a cam is all that is changed. The ideal range seems to be 1 to 1 1/2 turns after zero lash for a quiet valvetrain. However, up to 1 3/4 is within factory specs, I believe. One turn = .047 preload. If you only have one cylinder making noise it seems unlikely that it would be the cam or pushrods (since they are hardened)...that should be all cylinders, theoretically. It may be that a lifter is not pumping up. Just as a quick and free check...when you loosen the (noisy) rockers, verify that the pushrods are straight and clean/clear on the inside.

I just want you to know that I am not an expert but there are some on here that do multiple cam installs every month. I have tried to represent their information correctly and hopefully they will correct me if they feel I am misleading or not accurate.

vettenuts

iTrader: (4)

Start with a few basics. First, stock pushrods are not 7.400". Having stated that, this likely is not the issue.

Can you pinpoint it to one particular cylinder?

Can you hear it when you turn the motor over with the starter?

Did you check the underside of the valve covers for any contact with the rockers?

Does the car run OK otherwise? (If yes, then the likelihood of the timing chain being a tooth off is low)

When the valve covers were off, were there any rockers that didn't look like they were getting oil?

Did you clean the pushrods (inside and out) prior to installation?

Get a mechanics stethoscope and see if you can listen while the motor is running and pinpoint where the noise is coming from. It may not even be related to the valve train.

Have you listened to the injectors? Sometimes they can be noisy as well.

All aftermarket cams have smaller base circles. A smaller base circle doesn't indicate a "regrind". The smaller base circle is required to obtain the lift because the lobe can't be larger in diameter then the journals and therefore to obtain more lift the base circle is reduced. So don't sweat the regrind. Additionally, SDPC wouldn't sell parts like that.

SOMbitch

iTrader: (8)

I meant have a rocker nut back off. It has happened to me before......It's why I use loc-tite now

69ChBuLQ4

iTrader: (1)

The engine is on the stand and I have been cranking it over with a rachet. The valve covers are off and none of the rocker bolts are backed out. The clicking noise got quiet when it warmed up outside and I put oil on the valvetrain. Now, its colder and I turned it over to find the catch and click very loud and noticeable. The dots look like they are lined up fine, not a tooth off. Could be the valves hitting the pistons, but I feel like that would stop the cranking instead of being a "catch". I looked into the spark plug holes and saw what looks like a little rust. I hope the engine isnt crap . I might try to get a pic of the cylinders and see what you all think.

vettenuts

iTrader: (4)

Install a set of check springs on the cylinder you think is clicking. Turn it slowly until you just hear the click then press the valve stem down and check how much movement you have. Based on your description it sounds like a PTV issue. Did you measure when you put the heads on?

Johnv

Check for push rod clearance down the push rod holes in heads, in some cases with higher lift cams they can rub and require clearancing.

othewise just ensure you have correct lifter preload and adiquit piston to valve clearance (which should be fine with that cam on an otherwise std engine/ unmilled heads)

vettenuts

iTrader: (4)

Are you sure you are not just hearing the valves shut? Also, without oil pressure you may have bled out the lifters and slop in the valve train.

69ChBuLQ4

iTrader: (1)

The heads are the stock 317s, I didnt change or remove them. Only changed pushrods, cam, and springs. I'll try out the valvespring checker and look for pushrod clearance, thanks for the suggestions ill update tomorrow

69ChBuLQ4

iTrader: (1)

Just got out to the car today the weather has been freezing lately. Finally decided to take the heads off the engine and I couldn't believe what I found back in the problematic cylinder. DOODIE! How some mud got into the cylinder is beyond me. I have kept my engine in a room and sealed off the intake and exhaust ports since I bought it back in November. My brother thought that the salvage yard we got it from maybe didn't have it sealed off and a mud dobber got in there.
Anyways, I need to clean the carbon off the pistons and wondered what everyone recommended. Also, does the rust in the coolant passages look like a problem?

02*C5

iTrader: (1)

If it is surface only then it can be cleaned out, and I would clean it out as best as possible before putting it back together. if the rust is more than just surface rust you might be facing some issues really bad issues. Meaning your engine has "cancer" and it is worthless.

69ChBuLQ4

iTrader: (1)

I think it's just surface rust, the engine has pretty low mileage at 60k. Guess ill try to get down into the passages with steel pads or whatever fits. Can I use a high grit sandpaper on the pistons?

02*C5

iTrader: (1)

I would use carb cleaner a shop towel, or a soft metal bristle brush. Give a little more attention to the pistons that need it, make sure to get all the mud off, but remember anything on the surface will get blown out on the first fire.