2002Monster

GOT THE ENGINE STARTED!!!! but I have a HUGE knocking

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sound while running.....sounds catastrophic!!!!

I think I need to remove the head and see if the valves are bent.....

Could I be off just one tooth and have piston slap. now that the chain is tight on one side....I'm probably just off one tooth.....FUCK!!!

Any advice?

Anybody in Michigan, want to come and hang out on Saturday?.. Jake? Greg? Joel? Mike in Hamtramski?

Thanks,

02Monster

BTW.....the plugs were the reason why the bitch wouldn't start.....wrong ones.....freaking parts store guys....

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I was off by one tooth and it was easy to tell because the valves were way out of adjustment. The adjusters are easy to put out of place if enough pressure is applied from a piston slapping a valve. End result, bent valves and guides on a freshly machined head. Check your valve clearance, if you've got some that are way off, you've probably impacted a valve into a piston. Pull the head, get it redone, put it back on. That's what I did.

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Guest Anonymous
sound while running.....sounds catastrophic!!!!

I think I need to remove the head and see if the valves are bent.....

Could I be off just one tooth and have piston slap. now that the chain is tight on one side....I'm probably just off one tooth.....FUCK!!! Any advice?

Anybody in Michigan, want to come and hang out on Saturday?.. Jake? Greg? Joel? Mike in Hamtramski? Thanks, 02Monster BTW.....the plugs were the reason why the bitch wouldn't start.....wrong ones.....freaking parts store guys....

Bent valves usually amount to compression loss. The fact that the engine runs suggests to me the valves are not bent. Without hearing the noise I have no idea on what it is. It could be a lower end issue or a broken rocker, a timing chain that has not been tensioned, a 10 mm wrench left under the valve cover and so on.

The fact that you blame the parts guy on giving you the wrong sparkplugs is nonsense if you were the one who installed them. Didn't you gap them? Didn't you wonder if they looked like other plugs pulled from an M10 engine before installing them? What were the wrong plug numbers? These weren't extra long nose plugs that could be struck by a piston or even a valve?

I do not know off hand how many rotational degrees equal one tooth on the cam gear. But I doubt one tooth is sufficient to cause interference problems. I have used an adjustable timing gear in the past and although I do not think the amount of adjustment is as much as one tooth, it could be very close.

Good luck.

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before we all fly/boat/rail/drive/walk to

your house in Michigan to help you -

are you absolutely positive the spark plug wires and firing order

are correct ????

a poorly installed timing chain tensioner

can be your cause ?

an oil pump not pumping is another possibility ?

got oil pressure ?

remove the cam cover and crank the motor over without

the spark plugs and watch for oil flow from the oil tube

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Guest Anonymous

OOOooohhh. I like the idea of crossed plug leads.

Cylinders firing against one another can sure make for noise shaking and fun! So can plug leads that are not fully connected to the plugs or the cap terminals resulting in not all plugs firing or some of them misfiring!

Good one CD!

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I also removed the spark plugs so that the cranking would be easier...

Before all of the noise started happening, I was making oil pressure, becuase I would turn the engine over and the orange light would go off, I also noticed that oil was dripping from the valvetrain oiler tube above the camshaft.....

That being said, now that I crank it over with no spark plugs and the valve cover off, the orange light does not go out and I do not see any oil dripping out of the tube.....I cranked the car for over a minute...and before, the orange light would go out after about 10 seconds....

What could be incorrect about the chain tensioner?.....its in the slot on the insert, and the spring is installed. What do I need to look for.

The spark plugs are correct and the fireorder is correct also.....Die zundfolge ist, eine - drei - vier - dwei (1-3-4-2)

Tomorrow I will probably be taking the oil pan off and removing the oil pump to see if something is wrong...

02Monster

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OH BOY were working now !!

remove the oil filter and tell us what you find ?

I hope the filter is full - what kind of filter is it?

anything done to the oil pump or the pressure relief valvethat your not telling us ?

i wonder if the oil pump 'green' o-rings are in place?

- no o-rings and your loosing oil pressure down below ?

M10oilpumpparts02.jpg

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When I loosened the oil filter off, the oil leaked out...so the oil filter is full....its a Fram filter....I have a BMW black filter that I was going to swap out when engine was broken in.

Nothing was done to the oil pump pressure valve, etc and I made sure I had the o-rings put in.....

Its not new, but its a good used one with low miles...

Opinions? other than criticizing my German or my lack or double checking the parts guy screw up....( the Bosch plugs look the same, except the number on the side.

02Monster

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Geez, that's sounds awful Mike.. but slow down & plan a systematic way to find the problem.

If the timing chain was one tooth off, that's 20 degrees of crank, might not hit anything with a stock cam & pistons, but I don't know for sure. It probably won't run well, might act different if it was advanced or retarded by that much.

If you suspect bent valves, don't jump right to pulling the head first thing.

Do a leakdown check, if any valve is bent it will show up.

If you think it's oil pressure (sounds likely to me) don't pull the pump before you verify the condition with a known good mechanical gauge.

There's a lot of ways the oiling can stop on a fresh build, C.D. mentioned the weak points on o-rings and pressure relief.. What was done to the lower end, how clean was it? Did you yourself wash it after the machine shop hot tanked it? Cleaned out all the oil galleries with tube brushes? No excess sealant squeeze-out floating around? Even the new Fram filter is suspect, not worth saving a buck there with so much at stake.

Without knowing what was done, it's hard to speculate.. but please do the leakdown test & hook up a mechanical oil pressure gauge before taking anything apart.

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can you rent it at Murray's or Autozone?

When the shop did the block I didn't do anything extra to insure it was clean....in hindsight, it sounds like I should have.

I had oil pressure before I found out that the plugs were not correct...I would crank the engine while trying to start it and the oil pressure light went out.

The engine was completely rebuilt by me....12.5:1 pistons, new rings, new bearings (mains and connecting rod), new gaskets with no RTV or other sealers used, Schrick 292 cam.

I took the plugs out of it and took the cap off, so that it wouldn't fire up....it cranks unimpeded....so I'm also thinking its the oil pump and lack of pressure....

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I'm not saying this is the reason for your knocking sound, but you can't run 12.5 to 1 compression on 92 octane gas.

If you have bent valves, a compression test will show it. You don't need to get fancy with a leakdown test.

W. B.

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With 12,5 compressions one tooth off will hit pistons. Even less than a tooth is enough. Sounds like you haven't checked cam timing very carefully so that might very well be the cause. I don't think oil pressure is the reason if you haven't even run it more than a while. Although I can't tell why the pressure is now missing...

As John said take one step at a time to check the basics. Is it rotating by hands? Everything ok in the valve gear? How's is the cam timing? Compression test and leakdown test? Oilpressure check? And so on...

A rule that I have followed while building my engines is: "Trust no one"

Check every detail by yourself, then you know.

Tommy

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Guest Anonymous

Even before you perform a compression test or a leakdown test - confirm that the valve timing is set properly. If it is off as much as you think it is, given your revelation of very high compression pistons, Tommy is probably right about valve-piston interference.

You must have your reasons for running such high compression. I wonder about some of your measurements and the fit of these pistons. Are they forged? The point being that some forged pistons have a very loose fit until they reach operating temperature. This can result in piston slap. If you have several pistons "slapping" the noise could sound pretty bad.

You did not describe the noise other than it being catastrophic. Is it rhythmic?

Some additional things you could clarify: Does the sound occur just while the engine was running? If you crank the engine with the plugs removed, do you still hear the sound?

I am troubled by your questions regarding the tensioning of the timing chain. If you are unclear about this, how about the rest of the engine build?

The shop returned the block but you reinstalled all components. Was there any collaboration regarding the various measurements of bearing surfaces. I ask because there are other relatively common noises to consider like rod knock, or a spun main bearing, piston slap (mentioned earlier). Large bearing clearances make for noise and low oil pressure. You would do yourself a favor if you could localize the source of the noise with a mechanics stethoscope or even a length of hose.

Was the head resurfaced and/or the block decked? If too much material was removed, high compression pistons could easily interfere with spark plugs. Valves, with enough lift, at speed, could also kiss the tops of the pistons even without the valve timing being off a tooth. Resulting noises could sound pretty bad.

Out of curiosity, what style head gasket did you use with your high compression pistons?

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Guest Anonymous

Some more thoughts:

When the engine ran, how did it run? Were you able to set it up to run smoothly or were you preoccupied with the noise?

You have high compression and a camshaft that is far from stock. This combination rarely makes for a rolls royce idle. Were you able to get the engine to run at a fast smooth idle? Could it be that you have ignition timing that is way off base, causing the engine to fire in all directions? This leads me to wonder about another obvious source of "rhythmic" noise: a leaky exhaust gasket or two. The noise can sound metallic and deafening.

While I am at it, is the engine installed in the car? Is it possible the noise could be related to something interfering with the starter/flywheel/clutch assembly? Those are involve moving parts interference with which, by foreign objects or loose or improperly coupled parts, could also result in noise.

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These guys know way more than me, but I would think a few things. If the wrong spark plugs were also the wrong size, that could be bad during the initial startup. With the right plugs, did the engine run smoothly when it ran? Seems like it would be hard to start if the timing was off. A leakdown and compression check would answer some questions about internal damage. Honestly, it's all guesswork because there are so many variables. But I defer to the smarter guys.

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