W53 manifold gasket leak

[Stitebunny]

I have a W53 head with a dual sidedraft intake manifold and a long tube header. There is a coolant leak coming from that area and I suspect it is because the flanges on the manifolds have different thicknesses. It has washers securing the manifolds that are 'stepped' to contact each manifold. I have replaced the gasket and tried to match the washers to the manifolds for a good fit. But it still leaks. Is there anything else I can do? Or do I need to measure more carefully and get the washers to apply pressure more evenly?

Thanks for any ideas.

Another thought I had was blocking the coolant passages that go into the intake from the head. How important is the manifold cooling circuit? And would that plug off a cylinder head cooling circuit?

[Sealik]

Assuming the intake flange is thicker than the exhaust flange?

 

If so...you could remove the intake and shave the flange..as seen here.

....Intake on right.

 

[datzenmike]

The motor will run better if the manifold is at a constant (warm) temperature. This helps to vaporize the fuel. The coolant lines warm it up faster after start up and during the winter and prevents overheating from radiant heat from the exhaust manifolds on hot summer days. Best to run with them if you can.

 

Measure the intake and the header flange thickness and even them out. Otherwise the washer will tighten up on the taller one and the lower one will be loose.

[wayno]

IMO you want the coolant going threw the intake manifold, I have been running what you have for over 15 years with no issues, except I have a shorty header.

Do the thick/stepped washers sit at an angle when you tighten them down?

AS sealik has mentioned, if the washers don't sit flat, you can shave the intake, or you can add little strips of metal to the exhaust manifold, which is the more common way.

I have a queston, do you have studs sticking out of the head that you put nuts on to tighten the intake/exhaust manifolds onto the head, or are you running bolts into the holes in the head?

Another question, have you ever checked to see how flat the intake/exhaust manifolds are with a flat edge?

[banzai510(hainz)]

early headers used a thin flange thus the Hard to find stepped washers to get the even pressure. If your running a DCOE/Mikuni type sidedraft set up your not even using a water line anyway so best to plug the hole with a 1/4 pipe plug which is tapered.

 

If yu head already has the stock size water hole you can just use the tape tool and thread the head.Make sure to get a short tap as if too long it will hit inside the head so tou can get the correct taper when you put the pluggin. make save to do this a few times. put plug in till flush and shoould be OK.

 

If you have a SU set up then the manifold needs to be plugged up or fix the water leak.

 

YOu could try a Victor Renz intake manifold as if has a metal ring around the water passage.

 

If I remember right a W53 head might have never come with stock water holes so this could have been added so I dont know te hole size. I myself just drill a 1/4 hole if I run the stock intake with weber carb to heat it. So you maybe you find a smaller taperplug to fit.

[banzai510(hainz)]

Be honest those thin headers should be just thrown away and stick with the L16 manifold

[datzenmike]

Well now that Hainz has said it....

 

Other than weight what advantage do headers have over the stock manifold.... (that fits)

.

[banzai510(hainz)]

there is a newer version of the short tube header and a thicker flange and welded spacer they put on should work as sold by Top End Performance. I have one but have not used it.

 

I have the thin 1/4 Flange one that needs the special washes which I dont have r but just have it for looks now in the garage.

will sell for 25$ for those WHO just got to have it and dont want to listen to good advice

[Stitebunny]

Thanks guys.

Some answers;

The intake flange is thicker then the exhuast. It is a BRE intake that has cooling passages. I would prefer to run them as you guys suggest. And to not modify it if I can help it.

I also have a shorty header. Not sure of the flange thickness. I will check that.

The head has studs sticking out and I use the step washers with nuts. The washers don't appear to be obviously crooked when they tighten down. I'm guessing it's just enough off to not tighten the intake enough though.

I didn't check the flatness of the flanges but when I cleaned the gasket surface of the intake I ran it over some paper on a flat table and it cleaned up pretty evenly so I think it is probably okay in that respect.

[Stitebunny]

I have actually just purchased an L16 exhaust manifold. I got it for my other car with the short header. But maybe I will put it on this car instead and see if it is a better fit. I got it to quiet the other one down some. But if it will fix my problem here, I may have to find another one and ditch both headers!

[wayno]

I am not saying this is the best thing to do, but here I go.

I reuse my intake/exhaust gaskets a lot, if they come off the block, and intake/exhaust manifolds without any damage.

Usually the last time I re-use a gasket I put a thin bead of gasket material/silicone around the water jacket holes on both sides of the gasket and bolt it together, it usually takes at least an hour after I have it bolted on before I start the engine, and I am sure that isn't long enough for the sealing product to dry, but I have never had a leak before, but one could wait overnite I suppose.

Check for cracks in the intake manifold, I have never had a leak there.

It's good that you have studs, as you can tighten them tighter than a bolt going in a hole with aluminum threads, how tight do you tighten the nuts?

[banzai510(hainz)]

I use coppercote from Permatex and spray both sides. I reuse my intake gaskets also if I do a few swaps but only if they are recent otherwise I have a stack of new Felpro intales from O rilieys

 

If your head has studs esp on the lower side I would just tighten then up with the nuts.

 

But if you use bolts on the lower I would be careful on the lower as you dont want to stretch out the threads in the head. I would tighten the shit out of them and now I have proplems with loosen the bolts and the exhaust washers.(im running out)

 

I think standard thickness is .5inch of the manifold

[Stitebunny]

Thanks a lot guys. I inspected it today after work. The washers look pretty even to me. I checked the nuts on the studs and found them not as tight as they should be. I didn't use a torque wrench so I don't know for sure what the torque was. I usually snug stuff up and try not to over tighten. I'm not sure if I didn't tighten them properly last time or perhaps the gasket compressed a bit more. But I was able to tighten them down quite a bit more. I pressure tested the cooling system with no leaks. So I guess I'll take it for a drive tomorrow (probably to Golden Gardens) and see what happens. If it leaks again I think I will shave the washers a bit and use the sealant trick on the gasket. Thanks for all of the input on this.