11 replies to this topic

[merther]

About to replace the head gasket, any tips for the best way to seal it? I'll be using a bk450. Speaking to someone previously they recommended running the car to temperature with no coolant to seal the gasket. Is this a viable option?

[Bat]

Hi,

I'd say absolutely not! The heat won't transfer to the temp sensor properly due to the lack of coolant. I've never heard of sealing a head gasket before?

All the different vehicles I've worked on over the last 30 years have all been torque up and fill up... 

Cheers 

[Steve220]

Torque it down properly, run a heat cycle (with coolant) through it and then re-torque it.

Edited by Steve220, 17 June 2018 - 10:23 AM.

[sonikk4]

Normally run up to temperature, cool down, retorque head.

Somelse has mentioned heating up without coolant, seems very weird doing this. Never done it that way. Always done one full heat cycle, retorque and providing you have not got a poor copper gasket, jobs a good un. All with the correct ratio of coolant in the system.

[Mervyn]

I run mine in with pure water. Only adding coolant after 50 miles or so. Never had a leaky one yet

Merv

[RooBoonix]

With my GEG300 copper gasket I torqued down, filled with coolant, retorqued after driving to MOT and back and just kept running since. It's been fine.

Use a good quality gasket, and ensure your block and head surfaces are perfect and you should be fine

[Spider]

Somelse has mentioned heating up without coolant, seems very weird doing this.

 

 

That was likely me.

 

Most Gasket manufacturers will advise to fill with water only for a minimum of one heat cycle, but some recommend leaving the water in longer.

 

Also, if there's an issue and you have to remove the radiator or head again for some reason, all that good coolant is lost.

[Spider]

Here's what ACL say about Gaskets, including Head Gaskets. Q14 on page 3 and Q15 on page 4 deals with this issue;-

 

 

 

 

[Chris.Williams]

My instructions from Stuart at Vmax with my SC kit stated......

Start the engine initially without coolant , it may need a couple of throttle pumps to start as there is no choke but it should idle easily at around 1000 RPM , adjust idle speed as ness on the throttle set screw near the throttle linkage. Run for 40 secs then switch off and allow to cool then fill with coolant , this ensures the head gaskets seal to the head .

[Turbo Phil]

My instructions from Stuart at Vmax with my SC kit stated......

Start the engine initially without coolant , it may need a couple of throttle pumps to start as there is no choke but it should idle easily at around 1000 RPM , adjust idle speed as ness on the throttle set screw near the throttle linkage. Run for 40 secs then switch off and allow to cool then fill with coolant , this ensures the head gaskets seal to the head .

This^^
It allows the gasket face on the BK450 to seal properly. I was advised this years ago.

Phil.

[sonikk4]

 

My instructions from Stuart at Vmax with my SC kit stated......

Start the engine initially without coolant , it may need a couple of throttle pumps to start as there is no choke but it should idle easily at around 1000 RPM , adjust idle speed as ness on the throttle set screw near the throttle linkage. Run for 40 secs then switch off and allow to cool then fill with coolant , this ensures the head gaskets seal to the head .

This^^
It allows the gasket face on the BK450 to seal properly. I was advised this years ago.

Phil.

 

 

A bit more clarification. Once i have finished building my engine from scratch, 7 port head, reworked bottom end, pistons, crank etc etc and of course a brand new cam, whats the score with bedding the cam in. Rightly or wrongly i though once you have the engine going, you need to bed the cam in at 2000 rpm and keep it there for 20mina. Now with this bit at the beginning of starting the engine for 40 secs without any water / coolant in it whats the possible effect this could have on the cam??

[OzOAP]

My instructions from Stuart at Vmax with my SC kit stated......

Start the engine initially without coolant , it may need a couple of throttle pumps to start as there is no choke but it should idle easily at around 1000 RPM , adjust idle speed as ness on the throttle set screw near the throttle linkage. Run for 40 secs then switch off and allow to cool then fill with coolant , this ensures the head gaskets seal to the head .

This^^
It allows the gasket face on the BK450 to seal properly. I was advised this years ago.

Phil.

I do the same. Run engine with no coolant until you can feel heat through the head. Let it cool, then add coolant. The gasket has a lacquer on it to help it seal. This works better when not having to cope with coolant.