Engine blown or not?

[zkot]

So, went for a cruise (72 Bay) on Saturday in the sun with a mate only for about an hour or so not pushing it at all. Come Sunday starting her up, she struggles to start, once idling (badly) there is a huge amount of vibration in the van (as though one cylinder is not working) and the traditional whistle can be heard (even though she hasn't before!). Idling will only occur with my foot on the throttle if I take my foot off she dies quickly.

The engine has only done about 700 miles (refit over winter). Any ideas where to start the analysis or what may have gone wrong.

Thanks for any advice! ;-(

 

[rob]

start with the basics , plugs , points set correctly , air pipes in place not split etc. tappets set o.k ..... hopefully one of these is your problem

 

[Tofufi]

Check the current oil level and compression figures on all 4 cylinders.

Do / did both your warning lights work correctly?

 

[noddy]

Drop the oil, check for metal swarf, if you have much metal in the oil it will be a strip down to check crank and bearings for scoring.
I would also pop the rocker covers off and see if any of the valves are bent, you might have to take the valve rockers off to check for side to side play in the valves, also look for scorching around the end of the valve will indicate exhaust gasses getting past a valve guide.

It could also be a dropped valve, some time you can get lucky and the valve head gets stuck in the piston, I think this is unlikely as it usually happens at running speed and to a hot engine, but a kinked valve could be a cause even from a cold start.

Is there any chance the vibration is being caused by the fly wheel coming loose, have you taken the fly wheel off recently?

 

[zkot]

So tonight I checked the points (electronic!), spark plugs (were lose and gap not set great), everything else in place. Not sure about the tappets that will be tomorrow night! She started easier tonight for some reason and not so lumpy once started but still had problem idling and would run down immediately foot off throttle. Oil level is fine and is still clear (bearing in mind it was only serviced less than 100 miles ago!). Warning lights do not come on until engine stopped. As for flywheel, I suppose put on when engine fitted, start of the year and no problems until the weekend!

Rocker covers here I come! Not sure about compression (have to read up on that!) :-¦

 

[zkot]

Ok, last nights epic....checked all the tappets and they are ok. No scorching or anything else untoward in that area. 2 sets of tappets were way off though (2 & 4), lots of alteration.

So far checked: Plugs, points, leads, tappets, oil and all are checking out. Last night when I did start her up same thing: will idle as long as I have foot on throttle but as soon as I take my foot off she dies. Although vibration may have been a little less. I also reckon she gets hot VERY quickly, which I suppose might suggest extra wear in the engine somewhere....?!

So, yet to test cylinder compression (need to find a gadget for that).

Any ideas?

 

[noddy]

Running hot is going to be one of 3 things.

1 timing is off
2. tick over mixture is set way too lean
3 you have an air leak some where

My money is on the tick over mixture being set too lean what carb are you running? if its a stock solex the fuel screw should be between 2.5 and 2.75 turns out from fully home, the adjust tick over with the larger air screw to get tick over to between 800 to 900 rpm.

I would also check your timing, what dissy are you running single vac advance dual vac advance, 009 etc?

Might also be worth checking the plug to see what colour they are around the centeral electrode, white and scorched would indicate a lean mixture.

 

[K@rlos]

Sound's really lean like noddy said. If that does turn out to be it, get it tuned correctly because if there ain't enough fuel entering the combustion chamber, it will burn the next best thing.... i.e the crown of the piston. If your running twin carbs they can be an arse to get spot on. On my Webers i used a Gunsons color-tune and an air flow syncrometer. It's running a little rich but i'm booking it in on the rolling road, those guys will get tuned perfect

 

[VWAIRCOOLED]

My next step would be to isolate which cylinder isn't working.Get someone to hold the throttle at a steady low engine speed.Then you need to detach a plug lead in turn and note any engine speed change use some insulated pliers or two bits of wood to do this.The one or two which don't drop in engine speed have a problem which you will need to check.Make sure no one has swapped 2 plugs leads round for a prank if you engine was left un-locked.Check the firing order.
This check should take only a few minutes and will lead you to your diagnosis a lot quicker.
If you find a cylinder which isn't working doing this test then check that that cylinder is gettting it's correct spark,then correct fuel/air ratio (check for air leaks) then check compressions.If it's compressions and the valve clearances are ok you'll have to pull the head off-engine out time.

 

[zkot]

Ok, Checked compressions Cyl 1: 115psi, Cyl 2: 125psi, Cyl3: 125psi, Cyl4: 120psi. Also, pulled off each lead in turn with no change to engine noise etc! ;-( Timing was retarded, so brought that forward.

So with plugs checked, points checked, leads checked, tappets checked, compression checked...and all seems ok. Why do I have I this vibration..... that gets worse when I rev up and goes when I take my foot off the throttle and watch the revs die! She doesn't tick over, just dies instead, so other checks a little tricky!

Where else can I look?

 

[VWAIRCOOLED]

It's a hard one to diagnose without seeing it.When you say the engine had a refit,what exactly was done? Is it a standard 1600 twin port? What carbs are you running? When you checked the tappets did you turn each cylinder to the appropriate position?

When you pull a plug lead off the dizzy cap in turn you should be able to note a drop in engine speed ,you shouldn't get all 4 with no drop,but I appreciate it is hard to hold the revs steady and notice this when it won't idle properly.

 

[zkot]

'New' engine = recon from Remtec, standard twin port.

Tappets yep = half turn anticlockwise once found number 1 cyl firing position.

Trying to get the revs was more fun running back and forward, once putting a stick on the throttle!

Any more words of wisdon...., please?

 

[VWAIRCOOLED]

Check the condition of the fuel,make sure theres no dirt or water or any other foriegn substance in there.
What carb is on there and is it new,what make etc.

 

[WOLFSBURG-WERKS]

I hope this might be of some help.

If you have a standard TP 1600 Remtec engine then the chances are you will have a 009 dizzy. or did you buy a complete engine ?

It sounds like you have an air leak, this will be easy to check, you will need some easy start or simular liquid, must be very flamable! you will need to tick the engine over say around 2k, so set it up so you are happy it will stay around that revs, then take your easy start and i would check around the inlet manifolds all rubber joiners ...do not miss any part out !, including around the J clip!, the second place to check is the throttle linkage on the carb, make sure you spray it in the area the linkage enters the carb, then check the base of the carb, every place you spray make sure you are happy you have sprayed enough and covered the area well, also spray the ends of the manifolds, the part where they are bolted to the head, what you will be listening out for is ANY and i mean ANY change in revs, because you will be using a very flamable liquid if you have an air leak in ANY of the area's you have sprayed you will obtain a difference in revs. as soon as you hear your change you have found your problem, or at least one of your problems, you will never be able to tune an engine with an air leak, please post what carb you are running ?????, also please post what dizzy you are running ?????, you will do your air leak checks one at a time. also did you have any back firing ????,

Engine running hot is usually because it is running lean, chances are you will not be able to correct this untill you have corrected the air leak problem,

If you are running an 009 dizzy these do not run as advanced as they should, thus it will make the engine run hot, advance will not kick in untill around 1200 revs,

and i think the carb you will have on your engine might be a Bocar.

As for your vibration, it could be as simple as your gearbox mounts! check for any wear, check your engine is bolted up tight to your gearbox ! hope this helps with abit more info on what your running will be able to give more advance advice.

Danny.

 

[aogrady]

Hi!

Check the idle solenoid on the carb, this will stop it from idleing. And as for the vibration - check you haven't sucked a rag up into the fan!

Cheers!

Alistair

 

[zkot]

Thank you all for your advice...it turned out to be a split bellow between the manifold and carb! Once changed and retimed the engine, she runs ok now. ok, being less acceleration as the timing was so advanced...all good for now, of cruising now.

Just the temp to think about!

Thanks again for all your support and thoughts....one better educated dubber!

;-)

 

[VWAIRCOOLED]

Glad you got it sorted dude.
Do you still think it's getting hot? A good way to tell is after a drive turn the engine off and hold the end of the dipstick (whilst still in the engine) if you can barely touch it because it's too hot,you have an issue.If you can hold on to it,it's probably alright.

 

[zkot]

Yeah, I still think she's hot. I can't hold the dipstick.....and there is that 'hot' smell too. Having done all the other checks...theres nothing obstructing the fan and all tinware in place.

Maybe she's running lean as someone said...so maybe thats my next thought process...to the carb?

What do you think?

 

[noddy]

Could by your timing, what carb and distributor are you running, hot running is usual down to the engine over advancing when running along at cruising speed.

The only other things that comes to mind is that if you have a 34 pict 3 and an 009 dissy, have you blocked the vacuum ports on the carb, if not engine will suck air through these and result in lean running, and heat as a result. Also are all you engine bay seal in place including plug seal on HT leads?

Post you carb dissy combination and timing setting.

 

[zkot]

So its a 009 Dissy, 34 Pict 3 Carb. An AD coded engine. From what I can see the two vacuum ports are sealed on the carb with small tubes and screws on the ends. The tinware is in place except one hole where the oil bath filter overflow pipe would have gone (previous guy has put a pancake on). The timing is 27ATDC at 3000rpm.

What do you think?