1800 DX idle low (Update Now Sorted)

I have had the crank shaft seal and timing belt changed and now the car has been set up i find that the idle is running a little low.

Looking at the rev counter i think it is at about 500 rpm.

Can i just increase the revs where the cable meets the intake or will this mess up the co/air mixture without them being re set at the same time.

Cheers as alway

Andy

Adjust the screw at the back of the throttle body, that screw just does the idle speed, the CO adjuster is in the meter head so don't worry about adjusting this screw.
7mm spanner needed.
Brass screw in this picture (throttle body off the car)


If the idle keeps dropping on it's own you may need to change the O ring on the idle screw as that get's flat and hard so the screw moves on it's own.

Old o ring fitted.


New O ring

Thanks Mark

I replaced the washer a few months ago so will adjust and make the screw to make sure it is not still coming loose.

I was not sue if i started turning screws that i would make matters worse.

Andy

If the idle speed has changing during the cambelt change they may be a tooth out on the timing or the old belt could of been a tooth out and now it's it the right place, changing the timing will adjust the idle speed?
Might be worth to double check the timing marks.
Is there any difference in performance when driving or pinking noise?

Hi Mark
The car's performance is ok with no pinking noise, the only difference is the idle is low. I have had to put the car into the shed for the next couple of months as i am away back to work and won't be home again until September, and then it is MOT time so will get the CO checked and the idle set then. The trouble with only having the car on the road for a few months each year is i never really get to the bottom of things.
Andy

I would put money on the belt being a tooth out. Over time I've learned by my mistakes, do one thing at a time and if there's a fault go back to the last thing you touched, if you alter the CO and idle speed now you could mask the real cause.
Cheers

 

Thanks for the replies, if the belt is out a tooth is it a case of removing the belt, moving the offending pully until the marks line up and then put the belt back on. Then look at the timing and co etc.
Andy

Yes, belt, timing then CO and idle speed is the last thing.

OK a very big "thank you" again to everyone for helping me out here.
Andy

Timing marks for reference.
I painted mine white when I rebuilt my engine so they are easier to see.
There is also a mark on the dissy, If you remove the cap the rotor arm should be pointing at the line on the edge of the dissy and inline with the HT lead going to No.1 cylinder.

Bottom marks with cover removed.


Bottom marks with cover fitted.


Cam mark.


You can see where the bottom mark is in this picture.

Hello a bit of an update here. I know this is an old thread but i have finally been able to make  a start on looking at the timing my my car.

As you can see from the 2 pics when the crankshaft pully is lined up the cam shaft pully seems to be 180% out of line.

I am not sure if someone has put a pully out of sync. when it is like this the number one cylinder is at the top of its rotation as you can see it with the spark plug removed.

Any thoughts?

Andy

Turn the engine so the cam is right, timing mark at the front of the block and both valves are close, remove the dissy cap and check the rotor arm is pointing towards the line marked on the body and if you can remove the timing cap near the gearbox and check the fly wheel mark is somewhere near the pointer.

You have to remove the crank pully to get them cambelt off so it may be someone has put it back on in the wrong place, when you come to put it all back together just make sure the crank pully is in the right place.

When putting the bolts back on for the water pump, crank pully smear a little copper grease on them as it will make it easier to remove them next time.
I find if I leave the alternator belt on when undoing the water pump pully bolts its tops it spinning as much, be carful of you knuckles when the bolts come lose as I've hit mine a few times!
If any of the bolts are starting to round off replace them with new bolts.

turn the engine 1 full rotation on the crank and it should line up, your at the end of the exhaust stroke and needs to be on compression stroke. crank sprocket is half the size of cam

Thanks guys, I am going back to have a look tomorrow with a friend who is a mechanic. We will also fit the new fuel injectors and seals i have. Then hopefully get the car running right again.
Andy

Update on this one. I am glad to say the car is now running sweat. The timing marks were spot on when we did another rotation of the crank sprocket. We also fitted a new rocker cover gasket and added the splash tray under the rocker cover for the first time which should help keep the oil away from the gasket. I had been plagued with an oil leak so am now sitting fingers crossed these tweaks will sort that problem out.

We also fitted the new Fuel injectors. I get the brass ones instead of the steel ones to save a bit of money. New seals were obviously fitted and with a little oil around the seal went in a treat.

Getting the old injectors out was not to much trouble with the help of some mole grips and i bit to wood, oh and a large screw driver used as a pry bar. The fuel lines were quite rusty around the treads but the inner seals were good. New ones will be bought next month when i get some money.

Dizzy was adjusted slightly and the idle adjust fine tuned. The CO was good at the last MOT but when the weather is better i will also get that double checked.

We could not get the car on the road as the weather was bad today and i did not want to get the car soaked and then just left back in the garage.

Any how at the moment she is running sweater then i can remember, all but static in the garage.

Roll on a dry day so i can take her for a good blast to see how she goes.

A good days work i think Andy

The oil windage tray stops oil spewing out of the hole if the cap is missing.

It tends to pool the oil back to the scupper and away from the gasket.

The Big trick whether you used the one piece gasket and non-shouldered studs or the original Cork and rubber.

Only 2 drops of sealant (RED RTV) are to be used at the Cam over seal at th botton corners where the rubber meets the gasket.  

The other thing to know is that you seat the nuts not by tight but by torque… 87 in/lbs.  This is imperative to getting the Valve cover seal to not leak.  Too loose and the gasket leaks too tight and the Gasket will pucker at the top and collect oil till it leaks out usually at the rear where the splash is.  It won't matter if you havethe windage tray or not, too tight, and it leaks, too loose and it leaks, use any kind of sealant, and the gasket will slide and pucker and leak once installed.

Putting up with those since 1981.  Oh, the Cork ones usually last about 4-5 years and should be replaced, they will dry out and get hard crack and leak.

It only took me 3 gaskets in 5 weeks to realize that if I bought a torque wrench, and set it correctly it wouldn't leak.

Hi Briano

Thanks for the advice. I will get some red RTV and torque the nuts as i did them by feel.

Andy

you cant actually over-tighten the nuts enough to damage the seals (if properly made!) as the cork gasket studs have a shoulder on and the rubber type gasket have a metal washer built into the stud holes. the nuts will bottom out once tight, only thing you can do if over-tightening them is strip the threads

Mr Rubjonny
Thank you for the advice. I will leave alone and see how it goes. I am aware of not over tightening the nuts as the head thread can strip. Is it worth putting any lock tight on the thread or will that just make matters worse or some nylock nuts
Andy

I've never used a torque wrench in my life doing up rocker nuts/bolts, I just nip them up by feel. thread on till you feel it bottom out, then nip with a small spanner/ratchet.

if you dont like the sound of that then feel free to buy yourself a mini torque wrench, you want a small one for low torques such as this as the larger stuff isnt so accurate right at the low end of the torque range.

there should be no need to use locking compound or self-locking nuts if the stud and nut threads are good, once done up correctly they will stay done up