DanielH Posted February 7, 2023 Author Report Share Posted February 7, 2023 Morning, quick question: which of these exhaust valve should I order? a) https://www.jamespaddock.co.uk/exhaust-valve-unleaded-mk2149658 b) https://www.jamespaddock.co.uk/exhaust-valve-unleaded-2 The exhaust valve which I've extracted from my engine have a dia of ca. 1.266". thank you 🙂 Link to comment Share on other sites More sharing options...
johny Posted February 7, 2023 Report Share Posted February 7, 2023 The second item says for MK3 GT6 so, if youre sure what your engine is, the correct valve should be part 149658 as its indicated for MK2 GT6. The valve diameter you have stated is correct for a MK2 GT6... 1 Link to comment Share on other sites More sharing options...
DanielH Posted February 7, 2023 Author Report Share Posted February 7, 2023 Another question regarding the valve guides: Are these the correct ones for my mk2? https://www.jamespaddock.co.uk/valve-guide-inlet-mkiiiii-2 https://www.jamespaddock.co.uk/valve-guide-exhaust-mkiiiii-2 Also, my old exhaust guides had seals...are they required or can I leave them away? thank you 🙂 Link to comment Share on other sites More sharing options...
NonMember Posted February 7, 2023 Report Share Posted February 7, 2023 I'm guessing the five 'i's in a row means they're right for both Mk2 and Mk3 engines (I'm fairly sure the guides didn't change). The engine was designed not to have seals. If it's properly built (which it should be since you are fitting new valves and guides) then it won't need them. In fact, it's better without as you want a tiny dribble of oil to lubricate the guides. 1 Link to comment Share on other sites More sharing options...
DanielH Posted February 7, 2023 Author Report Share Posted February 7, 2023 While I am at it... would you recommend this head gasket? https://www.jamespaddock.co.uk/head-gasket-set-non-recessed-mk11111-2 thanks a lot 🙂 Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 7, 2023 Report Share Posted February 7, 2023 paddocks have a good reputation it shoud be as a Payen set be fine Pete 1 Link to comment Share on other sites More sharing options...
DanielH Posted February 12, 2023 Author Report Share Posted February 12, 2023 Evening! I've got a question regarding the engine's rear plate. When I took mine apart I noticed something strange: a pin was setting in the rear plate, and that pin gently pressed against the fly wheel. The foto below shows the pin and the wear mark on the rear side of the fly wheel. You can see that the face of the pin is blank and worn from the sliding surface of the fly wheel. The pin was somehow loose and just sat there in his hole. Anybody has got an idea what happened here? thanks 🙂 Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 12, 2023 Report Share Posted February 12, 2023 I have no idea but glad you found it i dont recall any holes that would need anything like that ... for what ??? heck knows what sort of noise that made when running Pete Link to comment Share on other sites More sharing options...
DanielH Posted February 18, 2023 Author Report Share Posted February 18, 2023 Good evening 🙂 I've got a couple of questions regarding the piston rings. a) Order the country pistons come with 3 grooves, which I am counting from the _top_ 1, 2, 3. 1 and 2 take the compressions rings 3 takes the oil ring triples. I can easily identify the order and orientation of the oil ring triples (I hope so...) I find the rings for grooves 1 and 2 problematic, because the don't have a TOP mark, only a part number is echted. Groove 1: the ring which is supposed to go into this groove has the chamfer INSIDE-TOP Groove 2: the ring has the chamfer on the OUTSIDE - BOTTOM Is the order and orientation correct?? b) Gap I've measured these gaps: 1, 2 groove/ring (compression): 0,20-0,25mm 3 groove/ring (oil): 0,25mm (the curled oil ring was impossible to measure...) The manufacturer specs says (for 75mm bore??): 1, 2 groove/ring (compression): 0,25mm 3 groove/ring (oil): 0,20mm So, am I on the safe side?? greetings 🙂 Link to comment Share on other sites More sharing options...
DanielH Posted February 19, 2023 Author Report Share Posted February 19, 2023 Morning, here's a sketch of the orientation and order of the rings, which I _believe_ is right: Happy for your input 🙂 Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 19, 2023 Report Share Posted February 19, 2023 2 reminds me of step rings the top ring was fitted with the step upwards to clear the ridge at the top of a worn bore pete Link to comment Share on other sites More sharing options...
DanielH Posted February 19, 2023 Author Report Share Posted February 19, 2023 Morning, I found these schematics here: https://www.rlengines.com/tech/Common_Ring_Types.pdf It appears that the first ring is a "Torsional Twist Compression" ring, the second is a "step-scraper compression" ring. Link to comment Share on other sites More sharing options...
DanielH Posted February 19, 2023 Author Report Share Posted February 19, 2023 Ok, a gentleman from another forum pointed me to this: Link to comment Share on other sites More sharing options...
johny Posted February 19, 2023 Report Share Posted February 19, 2023 As far as I can see everything agrees with the original instructions so think the ring position is clear. However the gaps is another topic and Im no expert but wouldnt want to go smaller than the manufacturers recommendation because of the risk of the ring becoming too tight when hot and breaking😲 1 Link to comment Share on other sites More sharing options...
DanielH Posted February 19, 2023 Author Report Share Posted February 19, 2023 Hello Johny, yeah, thats my concern, too. I've opened the compression ring gaps to 0.25 to 0.30mm. Link to comment Share on other sites More sharing options...
DanielH Posted February 25, 2023 Author Report Share Posted February 25, 2023 Good evening 🙂 just a quick update. The new "blue printed" oil pump has arrived, all clearances are really tight! Installed the piston rings per the guide. Arranged them in their grooves in such a way that they are in different sectors. Tightening everything down per the handbook. For my ease of mind I applied some locking paint: Link to comment Share on other sites More sharing options...
DanielH Posted February 25, 2023 Author Report Share Posted February 25, 2023 I am planning to insert the valve guides into the cylinder head tomorrow. Question: the new guides have different lengths: * short: 2,031" * long: 2,256" Which are for the exhaust valves, which for the intake valves? I am planning to use our household oven while the wife is away, to heat up the cyl. head. Is there anything I should know before I press them into the bores? thanks again 🙂 Link to comment Share on other sites More sharing options...
JohnD Posted February 25, 2023 Report Share Posted February 25, 2023 Inlets are the shorts Link to comment Share on other sites More sharing options...
JohnD Posted February 25, 2023 Report Share Posted February 25, 2023 Ps. No need to 'sector' the piston rings. They will rotate in theirs grooves in use, at about a thousandth of the RPM. So they won't stay where you put them. Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 26, 2023 Report Share Posted February 26, 2023 in the past ive just used a simple stud and washer to drag the guides in they are quite easy do they ever move , no idea but repaired a spitty which resembled a set of organ pipes all at differing heights Pete Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now