205 1.9 Stripped Thread In Block ...

[projectpug 0]

Hi all,

 

After breaking down on track, i decided to take the head off as it was showing low compresion.

 

I have a modified 1.9 8v using a flowed head with kent pt28 and kent double valve springs on a lightened and balanced bottom end . On taking out the lower centre headbolt to inspect the thread came out with the bolt .

 

The head seems to need new guides and vavlves due to light piston contact assuming this is what caused the breakdown.

 

The issue is how do i overcome the threads being stripped from the block?

 

Also would anyone like to hazard a guess at how much new valves and guides are with refitting hopefully to the block with the damaged thread?

Im based in the Wrexham area and would also like to try a slightly cooler cam than the current pt 28 i already have a pt23 to try sop resuming will need reshimming to suit too.

 

Thanks

 

Phil

[pug_ham 242 3 Cars]

You can get the block heli-coiled, most local decent engine remanufacturers should be able to do it or if you have use of machines you can buy a heli-coil insert kit & DIY.

 

I bought some new exhaust valve last year on ebay but I think eurocarparts listed them as well but do you need them all replacing?

 

Same goes for the head as the block, any decent engine remanufacturers should be able to do this but costs will vary between them so find a decent one locally.

 

I got the valve seats recut in a head last year at Drakes in Bradford for £20 but reground the valves for final fitting myself & also did the valve clearences.

 

You can swap the cam yourself easily enough & do the valve clearences yourself if you are handy with the spanners.

 

g

[DamirGTI 327]

The issue is how do i overcome the threads being stripped from the block?

 

Refurb with an helicoil insert set ..

 

Damir

[Miles 331 1 Cars]

Helicoils are a waste of time, I know that all the engineer's around here will not warrant them used in the Alloy blocks, I use time serts, basically a steel insert which really make the thread better than standard, Not cheap to buy the kit, around £140.00

[petert 554]

I have an Mi16 that has done 80000Km on ten 3D helicoils to keep the head on and two in the mains bolts.

[Tom Fenton 1,526]

I have successfully used Helicoils on alloy block head bolt locations. I guess it is down to how good you are at installing them.

[welshpug 1,627]

The local machinist/cylinder head specialist I use only uses timeserts now, they are stronger but more expensive, but as Tom said, a helicoil if done properly should suffice.

 

You can buy individual components to do the time sert, Wurth is a manufacturer for these, you'll find them on ebay amongst other places, though it'd be far easier for you to find someone to sort it for you.

[pug_ham 242 3 Cars]

If the block is in otherwise good condition a helicoil should work fine if its done correctly but if not then something better is needed

 

A friend is running an engine with at least two on her car & its been fine for the last three or more years since I fitted the engine.

 

If in doubt then choose a more permanent method of fixing.

 

I have a block here which had a thin external block wall due to corrosion that meant even a small torque pulled the helicoil out so a friend made a stainless plug for the bottom of the thread hole instead, possibly the same thing as the time serts Miles mentions.

 

g

[Miles 331 1 Cars]

A man I used to use for Helicoils did 2 Helicoils in the block which worked OK, the only thing because they are deep down is getting the tool in there, the timeserts just about reach there so care is needed

[projectpug 0]

Hi all, thanks for all the replies. A local engineering company is looking at helicoiling it for me. Its just the on in the centre so fingers crossed it should be ok