Cylinder head removal - timing marks and chain removal

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Riderz13
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Cylinder head removal - timing marks and chain removal

Post by Riderz13 » Thu May 02, 2019 3:17 pm

first time post and looking for some help while I strip my engine down to solve the low compression issue.
  • 1st question would be which cam marks i should be using to find TDC so that i can safely remove the cyl head, when i look at the end of the cams there are 2 notches about 5 mm in width but on the opposite side there a 2 corresponding stamped lines? i can get the stamped lines to line up at 3 and 9 o'clock but the 5mm notches do not look like they line up exactly!? I am guessing its one of the cams has jumped a tooth and is out of sync or its a matter of perspective and im just tripping out :)
  • 2nd is what is the best way to remove the cam timing chain as the manual has one step (3.10) about removing the cam journal holders then the next step (3.11) there is no chain in the photo and they are whipping the head off. is it a case of removing the tensioner to provide enough slack to slip the cams out? I am trying to avoid removing the cams and take the head off as one unit so is there a safe way to split the chain without destroying its integrity?
appreciate this has probs been covered in an old threads so please feel free to bump.

any help would be greatly appreciated!

moforockband
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Re: Cylinder head removal - timing marks and chain removal

Post by moforockband » Thu May 02, 2019 7:49 pm

Line the rotor up to the mark shown in the book, the exhaust cam mark (2) should be level with the head surface. It's then 20 pins back to the inlet cam '3' mark.
It won't have jumped a tooth, as these engines blow up if that happens. Piston - valve clearance is that tight.
The camchain is endless from Suzuki, so you have to remove the crank. You can however buy a rivet kit from DID. Measure your chain to check if it is worn, they are usually quite robust. The book shows you how.
The low compression will be either worn rings, or the valves all crusted up/seats worn. Do not buy ebay chinese piston rings!!
You can grind the valves in, but a better option for power is to get them re-cut with the std triple angle job.

You have to remove the tensioner, then cams, then head. You can feel with a finger if the bores are worn at the top of the piston run.

Riderz13
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Re: Cylinder head removal - timing marks and chain removal

Post by Riderz13 » Sat May 04, 2019 12:01 pm

thanks for the advice! so cams come out first then head off. was looking to re-seat the valves and check bores once its off

does anyone know of any good places to to get OE rings from in the UK if the ones from Ebay are rubbish?

"Line the rotor up to the mark shown in the book, the exhaust cam mark (2) should be level with the head surface. It's then 20 pins back to the inlet cam '3' mark".

sorry just to clear up. by rotor you mean the cam marks/chain wheels on the cams? or where you use the 17mm to turn the crank? take it the big notches should be facing inwards rather than outwards? i find the manual a bit vague on that in regards to removing the cams.

cheers :peace:

mechannibalism
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Re: Cylinder head removal - timing marks and chain removal

Post by mechannibalism » Sat May 04, 2019 7:05 pm

Use the mark on the crank-the arrow aligns up at the "T" (@9:00 ), the marks on the cam should align up ("3" pointing up on the intake and"2" pointing up on the exhaust). IF they don't align up you are 360 * out, turn the crank CCW one revolution. The lobes on the cam on #1 cyl. should be pointing at 11:00 and 2:00.... or there abouts.

moforockband
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Re: Cylinder head removal - timing marks and chain removal

Post by moforockband » Tue May 07, 2019 11:21 am

The cams spin twice for every crank rotation. Doublel check everything is correct before you rip it apart. You may find it is slightly off due to camchain stretch, easily sorted.
The ebay rings will not give you the compression you need, check on this forum for past woes.
Just to pre-warn, and I'm sure you won't, this engine does not take kindly to bodging/corner cutting. It's not a Honda :)

SevenThreeSeven
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Re: Cylinder head removal - timing marks and chain removal

Post by SevenThreeSeven » Fri May 10, 2019 3:20 pm

moforockband wrote:
Tue May 07, 2019 11:21 am
The cams spin twice for every crank rotation.
It's the other way around: the crankshaft spins twice for every camshaft rotation

I know that you know this, you were probably typing too fast.

moforockband
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Re: Cylinder head removal - timing marks and chain removal

Post by moforockband » Fri May 10, 2019 5:47 pm

hee hee, that's why my engine's so fast. thanks for the correction :D


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