Cylinder Head Bolts will not loosen
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From: VA
1988 300E, 1994 E320, 1999 ML 320, 2002 SLK 32 AMG -SOLD-, ML 350SE -REPOSSESED-
Cylinder Head Bolts will not loosen
Ok Im doing a head gasket repair and I can't get the cylinder head bolts out.
They loosened about a quarter of a turn for the ones that I tried but not all the way...
How do I get those damn things out?
They loosened about a quarter of a turn for the ones that I tried but not all the way...
How do I get those damn things out?
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They are tight...really tight...make sure you get the biggest breaker bar you have, or go buy one. If you are not using a breaker bar, just stop LOL. Even with a huge breaker bar you still need as much leverage as you can get.
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From: VA
1988 300E, 1994 E320, 1999 ML 320, 2002 SLK 32 AMG -SOLD-, ML 350SE -REPOSSESED-
Ok thats what im going to do tomorrow is get a breaker bar.
What do I do if I can't get them loose? Is there someone I could call out of the phone book or a tool that I could buy...
What do I do if I can't get them loose? Is there someone I could call out of the phone book or a tool that I could buy...
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From: REHOBOTH BEACH DE
88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
You can spray them with a penetrating oil and let them sit for a bit..
Heat sometimes helps also..
Then as Ps2cho posted, use the longest breaker bar you can get..
If still no movement, you can get more mechanical advantage by sliding a two to three foot length of pipe over the handle of the breaker bar.
Don't use too long of an extension on the socket as you want to keep everything square.
You can bang the breaker bar with a hammer to "shock" the bolt loose...
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Leverage makes a huge difference. If you are using a standard size 1/2" drive wrench there is no way in hell you are breaking those bolts loose unless you are incredibly strong. It just ain't gonna happen. Get a big breaker bar and go from there.
Remember upon reinstall there is a VERY SPECIFIC tightening sequence. Look at the FSM if you have not in regards to this. It is very important. Head bolts must be replaced FYI...they should not be reused.
Remember upon reinstall there is a VERY SPECIFIC tightening sequence. Look at the FSM if you have not in regards to this. It is very important. Head bolts must be replaced FYI...they should not be reused.
Last edited by ps2cho; Apr 2, 2010 at 01:33 AM.
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From: VA
1988 300E, 1994 E320, 1999 ML 320, 2002 SLK 32 AMG -SOLD-, ML 350SE -REPOSSESED-
Yeah im good to go on everything/sequence. Just can't get them out. Im goin to get that pipe today.
It said in the FSM to NOT spray or put any oils on the bolts because it might damage the crankcase.
I'll keep all that in mind if all else fails...
It said in the FSM to NOT spray or put any oils on the bolts because it might damage the crankcase.
I'll keep all that in mind if all else fails...
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From: REHOBOTH BEACH DE
88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
I'm looking at page 01.11011-415/7 SERVICE MANUAL ENGINE M103 MBNA # S-2421-103.
No mention of not using penetrating oil.
Don't know what chemically can even begin to cause crankcase damage.
Almost impossible for any amount sprayed at the base of the head to migrate to the crankcase.
Penetrating oil is standard operating procedure to remove any "frozen" bolt or nut.
Simple instructions:
"21. Slacken cylinder head bolts when engine cold in the reverse order to the tightening diagram, starting with 14."
May be difficult to break a center bolt loose versus the end bolt as the overall torque on the head acts like a belleville washer against the bolt head.
Again as Ps2cho stated, install all new cylinder head bolts as the existing may have a bit of stretch.
Good Luck.
Ed A.
No mention of not using penetrating oil.
Don't know what chemically can even begin to cause crankcase damage.
Almost impossible for any amount sprayed at the base of the head to migrate to the crankcase.
Penetrating oil is standard operating procedure to remove any "frozen" bolt or nut.
Simple instructions:
"21. Slacken cylinder head bolts when engine cold in the reverse order to the tightening diagram, starting with 14."
May be difficult to break a center bolt loose versus the end bolt as the overall torque on the head acts like a belleville washer against the bolt head.
Again as Ps2cho stated, install all new cylinder head bolts as the existing may have a bit of stretch.
Good Luck.
Ed A.
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Thread Starter
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From: VA
1988 300E, 1994 E320, 1999 ML 320, 2002 SLK 32 AMG -SOLD-, ML 350SE -REPOSSESED-
Haha broke two wrenches but got them all loose. I found a 1" galvanized scrap pipe on the jobsite today. Took it home tried it and worked like a charm. It just happened to have a slight bend in it which worked.
So Im guessing those 3-4 screws on the inside top side of the intake manifold to the cylinder head is whats keeping it attached now?
How do I clean the threads on the engine block? Im getting the cylinder head check etc. It says not to spray anything into the threads of the block is what I was trying to say on the other post.
Anyone know where I can find that brush locally that Samstag offers online?
So Im guessing those 3-4 screws on the inside top side of the intake manifold to the cylinder head is whats keeping it attached now?
How do I clean the threads on the engine block? Im getting the cylinder head check etc. It says not to spray anything into the threads of the block is what I was trying to say on the other post.
Anyone know where I can find that brush locally that Samstag offers online?
Last edited by loclark757; Apr 2, 2010 at 04:13 PM.
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Thread Starter
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From: VA
1988 300E, 1994 E320, 1999 ML 320, 2002 SLK 32 AMG -SOLD-, ML 350SE -REPOSSESED-
Dear ps2cho,
Man the UK thread is gone that ***** is toast. Someone took it off or Im not looking in the right place. What's the thread for it again? It explains what Im looking for...
Man the UK thread is gone that ***** is toast. Someone took it off or Im not looking in the right place. What's the thread for it again? It explains what Im looking for...
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MBWorld Fanatic!
Joined: May 2005
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From: REHOBOTH BEACH DE
88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
How do I clean the threads on the engine block? Im getting the cylinder head check etc. It says not to spray anything into the threads of the block is what I was trying to say on the other post.
Anyone know where I can find that brush locally that Samstag offers online?
Anyone know where I can find that brush locally that Samstag offers online?
Main reason they don't want you to spray anything on the threads is because it gives an inaccurate reading when you torque the new bolts down.
Find a small bottle brush which will work...
Thread Starter
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From: VA
1988 300E, 1994 E320, 1999 ML 320, 2002 SLK 32 AMG -SOLD-, ML 350SE -REPOSSESED-
Ok nice!
I understand the 13mm bolts that fasten the intake manifold to the head. Im going to get new wrenches tomorrow to do that. They look like a pain in the ***.
The 6mm screw holding the trans dipstick is not threading correctly and its not turning. Couldn't get it out today. Its all the way up against the firewall. WTF!...
Also is there such thing as taking out the head with the cam in one piece removed from the sprocket?
I zip tied the sprocket and timing chain together so I don't have to worry about setting it up again. Im trying to slip out the cam and head all in one piece...
I understand the 13mm bolts that fasten the intake manifold to the head. Im going to get new wrenches tomorrow to do that. They look like a pain in the ***.
The 6mm screw holding the trans dipstick is not threading correctly and its not turning. Couldn't get it out today. Its all the way up against the firewall. WTF!...
Also is there such thing as taking out the head with the cam in one piece removed from the sprocket?
I zip tied the sprocket and timing chain together so I don't have to worry about setting it up again. Im trying to slip out the cam and head all in one piece...
Last edited by loclark757; Apr 3, 2010 at 04:19 PM.
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Ah okay...I believe I just used a couple extensions until it was out to the air intake assembly scoop. You won't have enough room as you can see just with a socket + wrench. I remember doing the same technique for 1/3rd of all the intake manifold bolts as some are difficult to reach. You may need a universal joint too.
Thread Starter
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From: VA
1988 300E, 1994 E320, 1999 ML 320, 2002 SLK 32 AMG -SOLD-, ML 350SE -REPOSSESED-
Maybe try a long box wrench as well.
Do those 5 bolts have to come out completely or can they sit in there a little bit because it looks like they would be difficult to thread back in?
Do those 5 bolts have to come out completely or can they sit in there a little bit because it looks like they would be difficult to thread back in?
Thread Starter
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From: VA
1988 300E, 1994 E320, 1999 ML 320, 2002 SLK 32 AMG -SOLD-, ML 350SE -REPOSSESED-
Ok got those five bolts out. I just unhooked the idle control valve off its mount.
I got the first support strut bolt out for the Intake Manifold but, can't get the other one...It's really up in there.
Is it even terribly neccessary for me to get that other bolt out?
I got the first support strut bolt out for the Intake Manifold but, can't get the other one...It's really up in there.
Is it even terribly neccessary for me to get that other bolt out?
Last edited by loclark757; Apr 4, 2010 at 12:01 PM.
Thread Starter
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From: VA
1988 300E, 1994 E320, 1999 ML 320, 2002 SLK 32 AMG -SOLD-, ML 350SE -REPOSSESED-
Dear ps2cho,
Here's a pic of that 6mm Trans Dipstick mount screw...Like I said before the thread is gone im going to try a pocket knife next.
Got any ideas for that and the other intake manifold strut bolt?
I tried to put a pic of it up but its not working right now...
Here's a pic of that 6mm Trans Dipstick mount screw...Like I said before the thread is gone im going to try a pocket knife next.
Got any ideas for that and the other intake manifold strut bolt?
I tried to put a pic of it up but its not working right now...
