How do you time it after you change the gasket

Exactly which gasket did you change? There is a gasket on the valve cover and a gasket between the cylinder head and the engine block, the Head Gasket. It's the Head gasket you need to change. Then you need to flush the Oil system and the coolant system to clean them out.
Changing a head gasket is a Big job where you remove the top half of the engine exposing the piston tops. If the gasket has been changed 'several' times your probably looking at a cracked cylinder head or engine block, a VERY expensive repair. If this is the case it's usually easier to replace the whole engine.

You were here yesterday!

'year make model (engine size)' in that order and first three words in the question please.

You posted this question THREE times. You have to REFRESH the page to see if your question is posted. I deleted the duplicates.

Question moved from Office Equipment!

Why are you changing ALL the gaskets? You only change gaskets if they leak. You only change gaskets when you remove a part that HAS a gasket. It is only a 2020, nothing should need replacing.

There are no videos for changing gaskets, but you can find videos for changing a part that will include replacing the gasket.

https://www.google.com/search?q=2020+Kikker+HardKnock+125+replace+clutch

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You were here yesterday!

'year make model (engine size)' in that order and first three words in the question please.

You posted this question THREE times, make that FOUR!! You have to REFRESH the page to see if your question is posted. I deleted the duplicates.

Question moved from Office Equipment! Now you are in Cars and Trucks.

Why are you changing ALL the gaskets? You only change gaskets if they leak. You only change gaskets when you remove a part that HAS a gasket. It is only a 2020, nothing should need replacing.

There are no videos for changing gaskets, but you can find videos for changing a part that will include replacing the gasket.

https://www.google.com/search?q=2020+Kikker+HardKnock+125+replace+clutch

..

You were here yesterday!

'year make model (engine size)' in that order and first three words in the question please.

You posted this question THREE times, make that FIVE!!! You have to REFRESH the page to see if your question is posted. I deleted the duplicates.

Question moved from Office Equipment!

Why are you changing ALL the gaskets? You only change gaskets if they leak. You only change gaskets when you remove a part that HAS a gasket. It is only a 2020, nothing should need replacing.

There are no videos for changing gaskets, but you can find videos for changing a part that will include replacing the gasket.

https://www.google.com/search?q=2020+Kikker+HardKnock+125+replace+clutch

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If the gasket fits over the plug, I would guess it's the gasket for the plug for the oil pan. On cars/trucks, they recommend you change the gasket each time you change the oil (but few people or even garages do this).

Here's a link on timing cover removal. Repair Guides Engine Mechanical Timing Gear Cover AutoZone com Here's the gasket. Timing Cover Gasket 1975 Chevrolet El Camino 8 Cylinders 5 7L 2BL OHV...

Check the intake manifold gasket. If it leaks it will draw air into engine and this air bypasses the mass air flow sensor which will cause a rough idle or running symptom from running too lean. If you change the intake manifold gasket you should probably change the valley pan gasket at the same time. A dealer will change both for less than $500 and you might save some more if you dig around on GM Service website and find a coupon discount (Usually 10%-20%). You might save more at a local shop if you trust them and they do this type of work. Getting to the intake manifold gasket also exposes the valley pan and since you are already there it only takes a little more to change that gasket too. Some GM V-8 engines use a little oil between oil changes and if both gaskets are meticulously changed at the same time it will sometimes fix the oil usage. It did for me on my Tahoe (126k miles).

There is no set mileage to change a head gasket. You only replace the gasket if you have a problem with it. Change the timing belt as outlined in your owners manual. If you do not have an owner's manual, then call your local Land Rover dealer for the correct mileage to change the belt.

replace gasket put a pcv valve in it

do you have a 3.1L V6? The timing cover gasket seals the timing components, it is located behind the belt drive system (alt, a/c, p/s etc.) all of these components must be removed to change this gasket, also the oil pan lower seal gets changed at the same time. The oil pan gasket includes the rear pan seal and the side seals and on for the rear of the pan, the engine must be lifted out of it mounts to change this gasket. It takes time to do these repairs and each shop has an hourly rate per hour on labor. The cost of the parts will be relatively the same at any shop, labor will differ. I hope this helps to answer your questions.