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MD540iT's Avatar
 
Join Date: Mar 2003
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Loud noise from Cam tower!

Cross post from RL, see if there are any other ideas here.
So, heres the condensed story:
Just put the 951 back together after sitting for 12 years (new EFR turbo, custom exhaust).
Got it running last week for about 30 min, turned off and restarted with no issue, all seemed good. had a minor coolant leak at the turbo so I had to pull the intake off. to get at it.

put it back together, go to crank, and here a loud smacking noise! WTF is that?
Sounded like someone smacking the top of the cam tower with a hammer!
(its DEFINITELY not the injectors)

thought maybe it was the starter grinding, pull it, check it, all good there. have a friend come over and crank (pulled DME relay) Loud smacking sound coming from cam tower.
Oh no, did I drop something in the intake while it was off???

Well I pulled the plugs out, got a bore scope, checked it every which way and there was nothing in the intake. valves looked fine, no trace of anything or valves impacting pistons (top of pistons had a good layer of oily crud on top as it was running a bit rich, and the bore scope easily left marks in the crud)
hand turned the crank and at one point I felt a little more resistance don't know what that means.

SO, I pulled the cam tower, and everything looks fine, lifter buttons still firm, everything moves freely. all the valves are aligned and at the same height.


I can't find anything that would make that sound.

the ONLY clue I have is that with the cam tower off, I smacked of the lifters into the cam and that sound was similar., But I can't find any reason for it.
Old 10-05-2019, 05:57 PM
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Check that distributor rotor is held on by TWO bolts.
Old 10-05-2019, 06:11 PM
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Just let your lifters fully pump up. It will be noisy for a while, but smooth out eventually.
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Old 10-05-2019, 06:27 PM
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Quote:
Originally Posted by kdjones2000 View Post
Just let your lifters fully pump up. It will be noisy for a while, but smooth out eventually.
well I thought about that but it didn't sound like lifters, atleast not that ticking sound I have heard on other 944s, and I didn't hear that sound the first time it ran. didn't hear any valvetrain noise or injector noise.
again this was a LOUD smack sound. an OH ***** kinda sound.

so I kinda have 2 theories:
1. for some reason the valves were returning slowly initially and then would "pop" back up thus smacking the cam.

2. related to the lifters not being pumped up, could there be a "gap" between the lifters and the cam, and when the lobe comes around, it "smacks" the lifter?



Side note: when I first started the car last week, I flooded the cam tower with oil through the caps. (then closed them)
Old 10-05-2019, 10:46 PM
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Coeur d'Alene, Idaho
 
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Are you burning old gas here. ANY old gas? I ask because on a totally different car that had not run for a decade, I had your #1 happening but unlike you I had an easy way to tell as it was a pushrod engine. I pulled the rockers and a couple valves were sticking in their guides which I could see because they were not in line with the others.

It happened on cold startup each time after a fresh rebuild and I guess I did not clean the fuel system as well as I'd thought. First startup it ran fine and then the next morning cold - disaster. Replaced a bent pushrod and again it ran fine. Next morning cold - bam again. It's because the first startup was properly oiled valve stems, then the old gas varnish got into the valve guides but as long as the engine was hot it would not stick. Shut and cool and they're sticky on startup.

If this is the case the sticking can be so bad the guides can be pushed slightly into the cylinders as its gum/varnish that can form in mere minutes. I had rebuilt heads and before I resorted to pulling them, I sprayed a solvent on the valve stems from the removed valve covers and tapped the valves daiily for a couple minutes for a week before it dissolve enough. I also put Marvel oil in the fuel and oil and once I got it started with the issue not happening, I ran an entire tank of fresh fuel filled with cleaner through without letting the engine cool and seize valves.

For you, unfortunately you'd need to pull the cams to see if valves are sticking or operating smoothly. Anyhow that is my guess, I'll leave it to you to know how perfectly clean your entire fuel system is, or if there is tank varnish that's dissolving into fresh fuel, or if you boiled the tank out, etc.
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Old 10-05-2019, 11:40 PM
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Quote:
Originally Posted by IdahoDoug View Post
Are you burning old gas here. ANY old gas? I ask because on a totally different car that had not run for a decade, I had your #1 happening but unlike you I had an easy way to tell as it was a pushrod engine. I pulled the rockers and a couple valves were sticking in their guides which I could see because they were not in line with the others.

It happened on cold startup each time after a fresh rebuild and I guess I did not clean the fuel system as well as I'd thought. First startup it ran fine and then the next morning cold - disaster. Replaced a bent pushrod and again it ran fine. Next morning cold - bam again. It's because the first startup was properly oiled valve stems, then the old gas varnish got into the valve guides but as long as the engine was hot it would not stick. Shut and cool and they're sticky on startup.

If this is the case the sticking can be so bad the guides can be pushed slightly into the cylinders as its gum/varnish that can form in mere minutes. I had rebuilt heads and before I resorted to pulling them, I sprayed a solvent on the valve stems from the removed valve covers and tapped the valves daiily for a couple minutes for a week before it dissolve enough. I also put Marvel oil in the fuel and oil and once I got it started with the issue not happening, I ran an entire tank of fresh fuel filled with cleaner through without letting the engine cool and seize valves.

For you, unfortunately you'd need to pull the cams to see if valves are sticking or operating smoothly. Anyhow that is my guess, I'll leave it to you to know how perfectly clean your entire fuel system is, or if there is tank varnish that's dissolving into fresh fuel, or if you boiled the tank out, etc.
Hmmmm, now that you mention it. I didn't empty the system, I figured it was pretty low, so I put 3 gallons in and a little ATF.

BUT, I did have the fuel pump die before I first started the car. SO I pulled it apart and at the bottom of the fuel pump was this thick brown goo, it was like glue. I assume this is what you are talking about. ANNNNND I noticed (Now, but I didn't really look before) a little bit of this in the intake port.
SO maybe you are onto something. (actually I briefly though of this, but figured the "new gas" would wash it off. ) I did thrown in a couple bottles of injector cleaner and fuel system "conditioner" (but that was after I ran it)
Also I before I could start the car (the first time) I had to wake up the injectors manually and took a few tries before they sprayed.

I still have the cam tower off, how can I clean/lube the valves?
Old 10-06-2019, 12:05 AM
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Coeur d'Alene, Idaho
 
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I'm not there to see, but this sounds precisely like what's going on. I've been seriously wrenching as a hobby for 40 years, and am a former Worldwide Powertrain Planner for General Motors and did not have clarity on this until it happened. So, the valve stem/valve guide interface is super tight and lubricated by the fuel. Old fuel is this spot's absolute worst enemy and you definitely have that going on. You were smart enough to stop and wonder what's happening here.

To fix it, I recommend you remove the cams and the lifters/cam followers, whatever's atop the valve stems. Now without the cams presssing on them, check if one tip is lower into the block than others. I'm confident you will find that. Now take a brass hammer and go from one tip to another giving it a blow that slightly opens it and lets the valve snap shut again. Likely most of them will do this with a pleasing ring sound and one or more will sound dramatically different - a dull thump. Those are the gummed/siezed ones. Spray a fuel varnish cleaner (or Seafoam noted below) of your choice down there and let it soak. Do all of them because you are logical enough to know that the ones still movin also have gummy varnish, but the siezed ones were simply incrementally tighter.. Come back and tap on them periodically to help the cleaner work into the valves. Eventually they will all ring or sound consistent.

So now you've saved the engine from destruction.

The fuel tank has quite a bit of varnish that fresh fuel dissolves into gummy fuel. You need to either remove and clean the tank, or put a borescope in there, find the height of the varnish line (wherever the old fuel line was as it dried and left the solids) and fill the tank above that level with a strong mix of fresh fuel and my favorite - SeaFoam Motor Treatment. I am often bringing older cars back to life, so I buy it by the gallon container and you should for this project. Currently working on a red 1988 Toyota Supra 5 speed Targa that has not run for 12 years.

Take this advice or not, but empty the fuel tank. Then pour pure Seafoam in - maybe a quart with all the injectors out and in bottles. Turn the key on or whatever fires the injectors into the bottles. This will dissolve the sludge in the pump and lines (put a fresh filter on now and have a second on hand) with the full strength. Then fill the tank above the line you found with the borescope and enough Seafoam to have it at LEAST the maximum mixed strength. (I use 25% stronger routinely.

With the car level, several times a day go out and shake the car to agitate the fuel in the tank. After a week of doing this, plus tapping on the valves, you will dissolve the goo into liquid state. Drain off the fuel tank and the dissolved goo in it for use in your lawnmower. Refill it with fresh fuel of 5 gallons or so with the max concentration of the Seafoam. Take the fuel line off before the injectors and pump the pump and lines clear into a bottle so now the lines are clear. Now run the injectors into their bottles to clear the injectors without running the entire goo from the lines and pump/filter through them.

Now reassemble the engine and start it with the max concentration of Seafoam and go for a long drive. Do not let the engine get cold until you have run it for a solid hour. When you fuel up, put in more Seafoam so you are using the max dose for two tanks as insurance the valve stems are getting lubed (Seafoam has lubricants for this) and you ensure any remaining goo stays in dissolved state. Personally, I'd keep using Seafoam for several more tanks but frankly on the first cold morning startup if you experience no noise/issues you are out of the woods.

Sorry so lengthy but this is prefereable in a couple ways - no tank dropping and no head pulling. PM me if you need further input and I'll shoot you my cell.

Heading out to the garage to replace the original radiator in a 1993 Toyota LandCruiser I bought new that has 240k miles on it and has never been touched by anyone by me. Favorite car to work on by far!
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Last edited by IdahoDoug; 10-06-2019 at 10:16 AM..
Old 10-06-2019, 10:12 AM
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actually last night I started googling best way to clean varnish, seems acetone is best.
so I bought a gallon of acetone. Im going to drain the tank, and depending on how much gas is in there (since I put 3 gallons in) if its not much more then I put it, will help me guess how much varsnish is in the system.
But yes Im going to run the acetone through he system and the injectors then let it sit. then flush again, and see how it looks.

On the other hand im trying to figure out how to keep a valve open to clean it.


However I cannot go for a drive. A. the reason I am trying to get this car running is to get my daily driver, which is dead, in the garage (one car garage) since I have no car at the moment.
also its not registered, or insured at the moment, needs an alignment (just switched to late suspension). Best I could do is drive it around my apt complex, maybe just on the road in the neighbor hood behind me.
Old 10-06-2019, 03:33 PM
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Ok I have drained the gas that was in the tank, and its about the same that I put in, including a couple bottles of fuel cleaner whatever. (only idled it for about 20-30 min, so I couldn't have used much)
So the tank was either empty or very near empty.

the fuel looked ok, didn't see much of anything in it.
so can I reuse it?

also trying to figure how, what was sprayed on the valves got there? was it like a glob that got through the system or was it diluted in the fuel and slowly collect while it was idling? Now, noting that the original fuel pump got clogged with varnish, and the Fuel line that goes from the tank, to the pump, is the low point in the system.

maybe worth noting, the injector were out of the car while it was sitting
Old 10-06-2019, 08:27 PM
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Ok I think I can 90% confirm this is the case. I felt the valve stems and they were extremely sticky! SO what im assuming happened is that when the engine was running they were getting coated with a thin layer of varnish. When the engine was warm the gas would evaporate and leave the varnish was left behind, but while it was wet, it was ok, once it cooled it became very sticky and slowed the movement of the valves.
I drained the tank, and didn't get much more than I put in before I started it, so that means there wasn't much gas in there to begin with.(so I hope minimal varnish) I pulled the strainer (which by the way, was torn and very brittle the strainer material broke just by touching it!) There was a little varnish around the bottom of the strainer threads on the tank but only a few finger swipes worth. however it was quite liquid still, so hopefully can be easily diluted.
I then put a gallon of acetone in the tank, will drain it later today, and then run it through the fuel pump to the injectors and manually activate the injectors.

can anyone tell me if the injectors will stay in the fuel rail with out being held down to the intake?.
Old 10-07-2019, 01:36 AM
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Injectors should stay with fuel-rail since they are clipped in on that end.

For cleaning dried petrol varnish, you'll want fuel-system cleaner with healthy dose of PEA. Much, much better than Seafoam.

- Red Line SI-1
- Techron Concentrate Plus
- Gumout All-in-One
- 3M Max Strength Fuel System Cleaner #08814
- Royal Purple Max Atomizer 18000

Last edited by DannoXYZ; 10-07-2019 at 10:47 AM..
Old 10-07-2019, 10:37 AM
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Quote:
Originally Posted by DannoXYZ View Post
Injectors should stay with fuel-rail since they are clipped in on that end.

For cleaning dried petrol varnish, you'll want fuel-system cleaner with healthy dose of PEA. Much, much better than Seafoam.

- Red Line SI-1
- Techron Concentrate Plus
- Gumout All-in-One
- 3M Max Strength Fuel System Cleaner #08814
- Royal Purple Max Atomizer 18000
I got some Berrymans B-12, to start with, and lucas "upper cylinder lubricant and injector cleaner" going to put that in 2 gallons of fresh gas.

but the injectors are not clipped in, they are just pushed into the fuel rail
Old 10-07-2019, 02:15 PM
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Good to know on these recommendations, Danno - thanks.

On re-using the fuel, definitely not. It's dissolved some varnish, so the fuel now has more solids and ingredients for varnish creation than usual. Also, it's important to know for your math that the quantity of fuel you drained out was not the same as was put in there 12 years ago. Back when Obama was president, someone put an amount of fuel in it, then it evaporated down to whatever you drained out. So your goal in finding that varnish line is not to fill your fuel tank up to the lower amount but to try and fill it above the line. That's why I suggested a borescope or similar if you're not pulling the tank.

Sounds like you are on the right track so far.

Doug


Quote:
Originally Posted by DannoXYZ View Post
Injectors should stay with fuel-rail since they are clipped in on that end.

For cleaning dried petrol varnish, you'll want fuel-system cleaner with healthy dose of PEA. Much, much better than Seafoam.

- Red Line SI-1
- Techron Concentrate Plus
- Gumout All-in-One
- 3M Max Strength Fuel System Cleaner #08814
- Royal Purple Max Atomizer 18000
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Old 10-07-2019, 04:31 PM
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Quote:
Originally Posted by DannoXYZ View Post
Injectors should stay with fuel-rail since they are clipped in on that end.

For cleaning dried petrol varnish, you'll want fuel-system cleaner with healthy dose of PEA. Much, much better than Seafoam.

- Red Line SI-1
- Techron Concentrate Plus
- Gumout All-in-One
- 3M Max Strength Fuel System Cleaner #08814
- Royal Purple Max Atomizer 18000

hey Danno sent you an email did you get it?
Old 10-09-2019, 11:29 PM
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What day & time did you email? I need to narrow down timeframe. Thx
Old 10-10-2019, 04:14 AM
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Quote:
Originally Posted by DannoXYZ View Post
What day & time did you email? I need to narrow down timeframe. Thx
was a few days ago in the evening sometime, Ill PM you.
Old 10-10-2019, 04:51 PM
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ok latest update with some pics
I disconnected the line to the fuel pump.
Pulled the strainer and cleaned the inside best I could. there was some of the varnish which was in a viscous syrup like state. I'm assuming this is what made it through the system and was deposited on the vavles. I plugged the fuel tank and poured acetone in it. then drained that after sitting for a day, and cleaned the inside the best I could. There was still some solid deposits (which I tried removing with my finger, but it was on there pretty good), but I'm not too worried about that, it didn't seem like it was going too come out easily, so I put one of those inline see through filters, before the pump, should catch anything else.

So after I drained the acetone from the tank, I ran it through the fuel system, to flush out any solids that dried in the pump/lines. partly to make sure the pump and injectors still worked.

Next I took some fresh acetone and ran that through the system, I was hoping it would eventually come out of the injectors clear. But it still had a slight whiskey looking color when I was done.


NOW, I'm debating what to do. I have a fresh 2 gallons of gas (drained the 3 gal I had in there back into my 3 gal can, only had a 2 gal can left) Put a bottle of Lucas "upper cyl lubricant" and Berrymans B-12 (which apparently is mostly acetone!) in there 2 gal (might add some Marvel mystery oil I have half a bottle of.

So I have two thoughts/issues: Hoping to not replay this whole thing over again; What can I put in the gas to keep the valves lubricated? I'm assuming its going to take a few tanks to completely flush the system, so there will probably be some deposits on the valve stems no matter what, I figured if there is some lube on them, will help keep them from sticking.

Second, will it matter 2 gallons, vs half a tank? to dilute any varnish in the tank? or better to have a concentrated solution?

Last edited by MD540iT; 10-12-2019 at 05:46 PM..
Old 10-12-2019, 05:28 PM
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heres some pics
First you can see the deposits in the intake port.



Here you can see where I was flushing the pump/lines/injectors.


Heres the little tool I made to push open the valve to clean the valve stem.
Old 10-12-2019, 05:41 PM
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Injector clips are part# 930 111 388 00

Acetone is extremely strong polar solvent with bigger dipole-moment than ethanol. So don’t let it sit for too long before rinsing out of system with fresh petrol. Run pump with fresh petrol for 5-10min and that should be good.

Spray PB-Blaster on valve-stems to clean and free them up. Valve-springs are quite strong and if valve stays stuck open after release from compression with your tool, then it may be an issue. I doubt any of them will since clearance specs are quite large. Actually might want to compress them all first before cleaning to verify if any of them are indeed sticking.

Common source of burnt oil on back of valves is turbo centre seals, and valve-stem seals. Since you have new turbo, you can rule that out. Might want to poke valve-stem seal with precision screwdriver and feel how soft and compliant they are. Sitting for 12-yrs without oil may make them dry and crispy. Replace with fluoroelastomer seals (most durable & heat-resistant available).

Can actually do it without pulling head. Although I prefer to pull head and do valve-job and replace guides while I’m there. Also chuck new guides on lathe and mill some grooves to hold valve-stem seals. A lot of people have had seals pop off after replacement since factory didn’t use grooved guides. Engineer behind that and ones who did plastic ball-joint cups should be soundly beaten!!!

Last edited by DannoXYZ; 10-13-2019 at 06:19 PM..
Old 10-13-2019, 03:22 PM
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this head was ported by powerhaus, The PO had a too big turbo (also from powerhaus) that was on it I believe was leaking, as the reason I didn't drive the car is that I was getting smoke when letting off the gas, so I pulled the turbo, sold it, then couldn't afford a new one for a long time, then the custom exhaust for the dual V-band EFR...
Old 10-15-2019, 01:31 AM
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