New Marlin owner

[greyV8pete]

Re: New Marlin owner

The +20 and the +0.5mm on the top of the piston means 20 thou oversize. Make sure if you re-ring the pistons that you get rings of this size. I would anticipate that there will be slight corrosion at least where the rings have sat for so long. In any case use a glaze buster in the bores before fitting new rings. However if the corrosion is too deep then a rebore will be required.

[greyV8pete]

Re: New Marlin owner

The following link may help as it gives the engine code at which unleaded was factory fitted. Alas mine was too early, hence the rocky road of conversion! Peter.

https://www.burtonpower.com/tuning-guides/tuning-guide-pages/unleaded-fuel.html

[twinstacks]

Re: New Marlin owner

Thanks everyone. This engine has only done 12000 miles since it had its first rebore. There is no piston movement in the bores. I am going to take them out and deglaze the bores but would you recommend new rings? Not going to do the shells because if it really needs them I can do it at a later date as it’s not a big job and doesn’t need the engine stripped. What’s the collective thoughts.

Thanks again

[djj_engineer]

Re: New Marlin owner

Might I suggest that you do not use the device that caused the scratches in the cylinder head. The piston also shows these scratches. Also the cylinder head gasket used has overlapped the waterways perhaps the replacement does not.

[stevejgreen]

Re: New Marlin owner

Thanks everyone. This engine has only done 12000 miles since it had its first rebore. There is no piston movement in the bores. I am going to take them out and deglaze the bores but would you recommend new rings? Not going to do the shells because if it really needs them I can do it at a later date as it’s not a big job and doesn’t need the engine stripped. What’s the collective thoughts.

Thanks again

It rather depends on your budget and your forward plan, you can spend £100 alone on a set of +20 piston rings for all four pots at Burton Power!

If you start spending serious money you might as well continue to do so and do a full inspect/rebuild over the winter season.

[twinstacks]

Re: New Marlin owner

I received all the gaskets with the car so it’s only costing me time just now. I have stripped the valves out the head and they are just needing cleaned and recut. I will remove the pistons and check the rings are not stuck and then hone them to take the shine off the bores. The rest looks fine. As I said this engine has only done 12000 miles since it was rebuilt. It’s just rust with it sitting so long. The timing belt fell apart when I tugged it. Everything rubber is being replaced. The camshaft has the number K-355 on it. Does anyone know if that is standard?
Thanks again.

[HairyDave]

Re: New Marlin owner

My opinion, for what its worth. Do what you have to to get it running and put some miles on it. Then you will know what it needs and you will know a lot more about it.

[wiggiesworld]

Re: New Marlin owner

Re the unleaded head (if indeed it is). IMO I suppose you have to offset the cost of this with how many miles you intend to put on the car and what state of tune you anticipate the engine will have; as I'm sure you're aware the main reason for getting it machined for unleaded is to get harder valve seat inserted as without the good old lead in the petrol these are susceptible to more wear. I ran a little Dutton Melos for years using unleaded in an unmodified head and generally I was only doing a few thousand miles a year, with those kind of miles it would take many years for the valve seats to be impacted.

[twinstacks]

Re: New Marlin owner

Just going to rebuild head with standard valves and seats. I will put an additive in the tank as won’t be doing serious miles. Thanks.

[daveghunt]

Re: New Marlin owner

To check wether your head has hardened seats refer to Cabriobobs article posted in 2007. Ford Engines - Unleaded Fuel Info.
Might be difficult finding these heads in scrapyards, but the info still stands.

[greyV8pete]

Re: New Marlin owner

Just going to rebuild head with standard valves and seats. I will put an additive in the tank as won’t be doing serious miles. Thanks.

With the relentless increase in Ethanol in fuels, which burn hotter than non ethanol fuels, I would do the unleaded conversion now. It only involves having machining done to allow hardened seats to be pressed in for the four exhaust valves. You are going to have to grind them all in anyway so if the m/c shop do it then you will save that hassle too. Peter.

[twinstacks]

Re: New Marlin owner

Thanks guys.

[twinstacks]

Re: New Marlin owner

Well cylinder head all overhauled. Decidedto take pistons out and am glad I did. All the rings are stuck in the piston grooves so all freed off and will get built back up in next few days. Looking good so far. Chassis in need of tlc as bad with flaky rust. Was going to paint it with hammerite but have been advised against using that.

[greyV8pete]

Re: New Marlin owner

Well cylinder head all overhauled. Decidedto take pistons out and am glad I did. All the rings are stuck in the piston grooves so all freed off and will get built back up in next few days. Looking good so far. Chassis in need of tlc as bad with flaky rust. Was going to paint it with hammerite but have been advised against using that.

Good progress! I now use Rustoleum Combi Colour Satin Black. It smells and works like the hammerite used to before it went all “green” and it chips off. Make sure you use the combi colour version. (The stuff B&Q sell is no better than hammerite: same reason I guess). You may have to go to a decent proper paint supplier to get it. Peter.

[twinstacks]

Re: New Marlin owner

Thanks mate.