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nextgen Samba Member
Joined: August 19, 2004 Posts: 6008 Location: CONGERS, N.Y.
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orwell84 Samba Member
Joined: May 14, 2007 Posts: 2528 Location: Plattsburgh, New York
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Posted: Wed Mar 31, 2021 11:53 am Post subject: Re: Rebuilt stock 1.8L type IV engine noise after service. |
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I have had an exhaust leak develop a number of times from the head. It happens after installing an engine and putting the heater boxes on from underneath after. It’s hard to get a good straight shot and keep the copper gasket lined up and feel for a good seal. The other problem I have had is after installing an engine it’s great and I forget to retorque the head....so I end up doing it after the header has loosened up and is getting noisy. At this point the gasket has shifted and I end up pinching it. The noise goes away but upon rebuildI find a pinched gasket and carbon from an exhaust leak. Even a good mechanic could fudge getting the headers to seal. The oval gasket is not the greatest arrangement. |
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Vanapplebomb Samba Member
Joined: November 03, 2010 Posts: 5389 Location: Holland, MI
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Posted: Wed Mar 31, 2021 1:10 pm Post subject: Re: Rebuilt stock 1.8L type IV engine noise after service. |
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nextgen wrote: |
Yes Vanappplebomb,
From experience those exhaust seals are sometimes tricky to set in place while trying to get the header especially with a heavy T-4 heater box on it.
That is why as mentioned I put the gasket in place with a drop of crazy glue..
BTW the black line as you mentioned will cut through the gasket in time. |
You are spot on with glueing the gaskets to the head. Definitely the best way to stick those gaskets on is with a drop of Crazy Glue, Super Glue, etc. definitely my go-to method as well. Holds them up in the recess, and keeps them from shuffling around on you when fitting the exhaust in place. _________________ 1800 Type 4 Berrien 295
http://www.thesamba.com/vw/forum/viewtopic.php?t=487021 |
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Sawyer2 Samba Member
Joined: September 22, 2019 Posts: 62 Location: Billings, Montana
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Posted: Fri May 14, 2021 7:07 am Post subject: Re: Rebuilt stock 1.8L type IV engine noise after service. |
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1 month and a half later, and two trips to the mechanic and I'm still having issues unrelated to the original issue I brought it to them for.
Back story, had my engine rebuilt last year and everything was going really well, very reliable, and in just the shape for me to start working on the interior/exterior. I noticed a small drop after every drive so I took it to the mechanic to have it sealed up.
After them having it for three months, I finally got it back but it had what sounded like an exhaust leak. I told them I couldn't stand to drive it sounding like that and was told to put 500 miles on it and bring it back in. So after about two weeks, with less than 100 miles I called and said I can't drive it anymore, I don't like the sound it is making and was happy before I took it in. Also, the leak is still there, not as bad but still present. So I brought it back to them and in a couple of days, they called to have it picked up. When I picked it up, it sounded like new! Everything seems to be back to normal and I had my new RPM and Oil temp gauge working so I was excited to start tracking the data and see how I can improve my driving and bus as time goes on. I noticed the bus idles right around 970 RPM and when fully warm around 990-1010 RPM it was nice to see that trend. The temperature around town would get up to about 145-150 degrees and out on a 40-mile drive cruising about 65, it hovered around 180-190 degrees.
Unfortunately, after a week or so, I started to hear the same noise as before. I'm stunned, I have been extremely light on the gas and never pushing the limit in any gear. I'm just tired of bringing it out to the builder who is 25 miles away and then I usually need a ride to and from, and so on. But I went ahead and called him, I told him I'm ready to start working on this issue myself, I said the sound is back and I'm not too happy about it. I just want my engine to sound normal and I'm going to either replace the heater boxes or troubleshoot the leak myself. He said he wanted to take a look and requested I bring it back in next week. I have also noticed my RPM at startup is now around 790-840 RPM, lower than before. When it is warmed up it is around 920-940 RPM.
In the meantime, I wanted to investigate. I took it for a quick cruise to get to warming temps when the sound is quietist or the engine is overpowering the sound. I used a hose to hear around the engine while it is running and I'm not that great at it but I think I am still hearing a sound coming from the #3 cylinder. So that is consistent with the last time I did this test. So I decided to check the spark plugs and see if I removed the plugs one at a time if I would notice a difference. I started with the #4 cylinder and come to find out the plug is broken! The part that snaps onto the tip of the spark plug is intact but the cover around the plug is broken and looks like it was touching something hot. With the #4 plug removed, the bus ran roughly like it was not balanced, and then I forgot to pay attention to the sound. I replugged the wire and proceeded to the #3 wire, it was not broken like the #4. When I removed that and started the bus, I could hardly tell that it was removed... It was not like the #4 when I removed that wire. Does that point to any significant issues?
Sorry for the delay in staying on top of this post. I recently started a small business that has required a lot of my attention but I plan on doing better to sort out my issue.
Sawyer _________________ Sawyer
IG: @toptier_discgolf
1971 VW Transporter Deluxe (sold 2020)
1972 VW Sportsmobile Camper (sold 2012)
1975 VW Transporter FI (sold 2007)
1976 VW Transporter 1.8L FI |
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GARRICK.CLARK Samba Member
Joined: June 30, 2012 Posts: 1267 Location: Lancashire UK
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Posted: Fri May 14, 2021 7:32 am Post subject: Re: Rebuilt stock 1.8L type IV engine noise after service. |
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If you remove any of the 4 leads and the motor sounds the same then the cylinder with the pulled lead isn't working. Maybe the head is loose creating a chuffing noise.
If the head isn't torqued down you'll loose compression.
Head studs threads don't usually fail on a type 4.
You will need to check head torque numbers,but it's hard to get at all 8 nuts with motor still in the vehicle.
Check tappet clearances |
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Sawyer2 Samba Member
Joined: September 22, 2019 Posts: 62 Location: Billings, Montana
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Posted: Fri May 14, 2021 7:58 am Post subject: Re: Rebuilt stock 1.8L type IV engine noise after service. |
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GARRICK.CLARK wrote: |
If you remove any of the 4 leads and the motor sounds the same then the cylinder with the pulled lead isn't working. Maybe the head is loose creating a chuffing noise.
If the head isn't torqued down you'll loose compression.
Head studs threads don't usually fail on a type 4.
You will need to check head torque numbers,but it's hard to get at all 8 nuts with motor still in the vehicle.
Check tappet clearances |
I will check the lifter clearance today and also do a compression test. I spoke to the builder this morning and let him know of my finding. He was surprised to hear about the broken spark plug wire and mentioned again to bring it in. _________________ Sawyer
IG: @toptier_discgolf
1971 VW Transporter Deluxe (sold 2020)
1972 VW Sportsmobile Camper (sold 2012)
1975 VW Transporter FI (sold 2007)
1976 VW Transporter 1.8L FI |
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GARRICK.CLARK Samba Member
Joined: June 30, 2012 Posts: 1267 Location: Lancashire UK
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Posted: Fri May 14, 2021 8:00 am Post subject: Re: Rebuilt stock 1.8L type IV engine noise after service. |
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They are fragile those plug ends. It might of broke when he fitted it and didn't even no it had happened |
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raygreenwood Samba Member
Joined: November 24, 2008 Posts: 21474 Location: Oklahoma City
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Posted: Fri May 14, 2021 12:56 pm Post subject: Re: Rebuilt stock 1.8L type IV engine noise after service. |
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GARRICK.CLARK wrote: |
If you remove any of the 4 leads and the motor sounds the same then the cylinder with the pulled lead isn't working. Maybe the head is loose creating a chuffing noise.
If the head isn't torqued down you'll loose compression.
Head studs threads don't usually fail on a type 4.
You will need to check head torque numbers,but it's hard to get at all 8 nuts with motor still in the vehicle.
Check tappet clearances |
^^^^^^ this......and......make SURE the builder is not using the factory head gaskets.
The sound.....from your description....along with no power from #3....sounds like a leak at the head.
Yes.....could be a torque issue....loose nut or pulled thread on head stud (rare on type 4 as Garrick noted)..... Could be a piece of debris caught between head and cylinder.
Could be the case needed to be decked and was not. Could be cylinder seats in head, flycut out of plane.
Could be the use of those damn head gaskets.
Ray |
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GARRICK.CLARK Samba Member
Joined: June 30, 2012 Posts: 1267 Location: Lancashire UK
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Posted: Fri May 14, 2021 1:06 pm Post subject: Re: Rebuilt stock 1.8L type IV engine noise after service. |
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Seeing as the heat exchanger flanges at the ports don't look sooted up from an exhaust leak my thoughts are gasses leaking from the head seal.
Hope not.
Comp test on will tell a lot. |
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