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202 inlet manifold question?

Drewie

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Have a VC 202 which has been fitted with extractors many years ago due to a warped manifold, I have had to pull the extractors and inlet manifold off to replace a starter motor. I know on the original cast iron exhaust the inlet and exhaust manifolds were bolted together and there was a valve that let hot exhaust gases into the inlet manifold to warm the inlet manifold when the motor was cold, from what I remember that valve set-up was on the right of the carby. When I took off the manifolds I noticed that the exhaust people had blocked of the inlet into the inlet manifold with a thick steel plate, I thought yep I know why the did that, but then I noticed the same hole on the left side of the manifold which they have left uncovered, was wondering why they would have blanked off one side and left the other open. I don't think it matters as the inlet manifold appears to be a double skin type of casting and the holes or ports only appear to go to a chamber that is designed to heat the manifold on cold starts.
This car runs faultless during the warmer months but when the cold weather hits it tends to stall until up to temp due to having no heating of the inlet manifold. was wondering if these holes or ports could have something to do with the cold weather stalling. ie one blanked off the other open?
 

Tom_1569

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Wow, im quite confused lol.

First you dont need to remove the manifolds to replace starter motor.

Can you post pics of what is blocked off and what isnt?

The EGR Heat valve, was originally fitted fromn the exhaust headers to the aircleaner (activated by vacuum on the air cleaner), most after market extractors do not have this fitting, so it is common practice to blank it off at the air,cleaner or even fit an aftermarket air cleaner.

Unless your car has this setup, then yes cold morning's are always going to be a bitch until its gets up to temp, I have heard of people implementing there own alternative, but it justs seems so far fetched and alot of work, can or do you have a choke?
 

Drewie

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The standard original inlet and exhaust manifolds are bolted together ie if you remove them they come off in one piece, you can then unbolt the inlet from the exhaust manifold, where the 2 manifolds join there is a passage way that lets a portion of the exhaust gas actually pass into a cavity on the inlet manifold to warm up the floor of the inlet manifold, there is a passage way between the 2 manifolds which allows this gas to flow, one is blanked off the other has been left open by the people from the exhaust company. Nothing to do with the hot air box that runs from the exhaust to the air cleaner.
I was wondering if both these openings should have been blanked off, they are on the underside of the inlet manifold and are not visible until the inlet manifold is removed and turned over.

I did have to remove the extractors as there was no room to manuevre the starter motor out, as it was almost touching the extractors so it had no movement at all, it is the original Lucas starter motor which is quite large,
not the Bosch one which is also used.

I will see if I can post a pic of the area.

If you look at the lower pic of the exhaust manifold you will see 2 holes one at either end, there are 2 corressponding holes in the underneath of the inlet manifold, that is what the small gaskets in the pic are for. I really don't think it effecting it as it has been like this for several years and runs fine except for the cold weather stalling, was more interested why they would have blanked one off and left one open when they fitted the extractors, I will just refit it as it came off I guess.
 

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CSD

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Know exactly what you are talking about. It is referred to as the hotbox.
You can get extractors that have te attachment to let the exhaust into this area but there is no valves. Just a constant flow.

I wouldn't worry about it too much. I had the same problem when I put extractors on mine. It does definitely take longer to warm up now as mine stalls a couple of times till it is warm also.

As for them blanking only one side, remains a mystery. Won't effect anything you don't have to blank either of the holes off if you don't want. As you said it is just a cavity in there and won't effect performance in any way.

My extractors run really close to the starter as well. I hope my starter motor lasts for a long time, because it will be a bitch to get out.
 

Drewie

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Know exactly what you are talking about. It is referred to as the hotbox.
You can get extractors that have te attachment to let the exhaust into this area but there is no valves. Just a constant flow.

I wouldn't worry about it too much. I had the same problem when I put extractors on mine. It does definitely take longer to warm up now as mine stalls a couple of times till it is warm also.

As for them blanking only one side, remains a mystery. Won't effect anything you don't have to blank either of the holes off if you don't want. As you said it is just a cavity in there and won't effect performance in any way.

My extractors run really close to the starter as well. I hope my starter motor lasts for a long time, because it will be a bitch to get out.
Thanks mate... I thought it would be ok, just confused me a bit as to why one side was blanked off and the other left open, I had no option but to remove the extractors to get the starter motor out, I managed to unbolt the starter but it had about 1mm of space from the back of the starter to the extractors, absolutely no room to pull it back to remove from the motor, I could rotate it back and forth but was almost resting on the extractors, it must have been ok with the heat tranferring as the extractors have been on for over 5 years and no issues until recently, just think the starter died of old age.
 

jakbob

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Well if both holes were blocked off it would make sense because apparently sometimes the floor of the inlet manifold can corrode and get pinholes in it which lets exhaust gas into the inlet manifold all the time and makes the engine idle rough.
 

Drewie

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Well if both holes were blocked off it would make sense because apparently sometimes the floor of the inlet manifold can corrode and get pinholes in it which lets exhaust gas into the inlet manifold all the time and makes the engine idle rough.
Good point there 'jakbob' as they are getting pretty old now I guess that is something that could happen, might see if I can find something to block it off with.
 
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