Sticky valves on a Pinto 2.0

[Emily]

Hi has any one had any experience of sticking valves on a 2.0 Pinto engine. I have a very rough idle and tested the system with a vacuum guage which shows a fluctuating reading which when you investigate further it says the likley cause is sticking valves. The engine has only done 3000 miles since 2001 so I am guessing the valves are gummed up. Has anyone tried addatives as I would like to try this before stripping the engine to put it right. If you have please let me know what you used.

[CompoSimmonite]

Re: Sticky valves on a Pinto 2.0

Take the rocker cover off and turn the engine over by hand (easier if plugs out !). At same time check each cam follower clearance. If a valve is sticking then expect a massive gap. If just normal gaps then more likely a burnt out / damaged valve. If the engine has done such low miles then it could also be piston rings stuck due to lack of use / standing.
To be honest you would best doing a compression test before anything else.

Paul H

[greyV8pete]

Re: Sticky valves on a Pinto 2.0

Hi has any one had any experience of sticking valves on a 2.0 Pinto engine. I have a very rough idle and tested the system with a vacuum guage which shows a fluctuating reading which when you investigate further it says the likley cause is sticking valves. The engine has only done 3000 miles since 2001 so I am guessing the valves are gummed up. Has anyone tried addatives as I would like to try this before stripping the engine to put it right. If you have please let me know what you used.

Depends what you mean by a fluctuating reading. A sticking valve usually gives an occasinal drop in the vacuum. If the fluctuation is more frequent it may just be mirroring an erratic tickover. With a straight through type of silencer a burnt exhaust valve will normally give one noticably loud pulse in the exhaust beat and the power will be dramatically down.

My 2.0GL Sierra valves were loose rather than sticking but at 80k miles a new set of valve stem seals cured the "puff of blue smoke after decelerating" effect.

Are the valve springs new or old ones re-used?

As Paul says a compression test would be my first check too. Then try re-checking after putting a few squirts of oil down the plug holes, which will temporarily seal the pistons better, to assess possible piston ring problems. Peter.

[Emily]

Re: Sticky valves on a Pinto 2.0

Everything on the engine was new 3000 miles ago as it was bought as a brand new engine. But it has had very little use over the years. The engine has plenty of power and runs smooth at revs just lumpy on tickover, so when driving along doing 1500 rpm have to change gear and keep the revs up to give a smooth ride. I tried pouring ATF down the carb last night as this was recomended to me. Drove the car to work today a good 30 mile run and seams a lot better but not perfect. Will see what its like after the journey home. I May end up taking the head off and re-seat the valves etc and check if everything is as it should be. Think its mainly just lack of use over the years.

[cameronfurnival]

Re: Sticky valves on a Pinto 2.0

a quick and dirty test is to squirt some penetrating oil into the inlet manifold and if the gauge then shows a different reading by not dropping back then the valves are almost certainly the problem.

[Emily]

Re: Sticky valves on a Pinto 2.0

Well it was the valves in the end, removed the head and exhaust valves were caked in black crap cleaned up reseated valves and rebuilt her, she will now tick over at 600 rpm sweet as a nut. Like driving a new car, responsive, quieter. And whats best is the sun is shining so time to enjoy...

Thanks for all the advice.