I have volvo penta md6b inboard diesel. When I would start it up it
would run right up to 2200 rpm's when in neutral. But when put in gear
it would only go up to 500 rpm's and take about 15-20 minutes before it
would go up to 1500 rpm's.Max rpm's shoould be about 2400. Then one
day I accidently left I forgot to open the raw water inlet value and
overheated the engine. I had a so-called mechanic come out and told him
the situation. He found water in the oil but said it was not a head
gasket problem but was due to water back siphoning through the exhaust.
He changed the oil several times to get the water out and said it
should be fine. When I went out again I still had the rpm problem so he
never even addresed that correctly. I decided to dive the prop and
removed and incredible amount of barnacles. However the rpm problem
persisted and I checked the oil again and found WATER in the oil AGAIN!
The engine does not overheat but am I right in thinking it is the head
gasket? If so are there any manuals that explain how to replace the
head gasket. I'm tired of paying overpaid mehanics who don't know what
they are doing and don't show up half the time.

thanks for any help

wrote in message
ups.com...
I have volvo penta md6b inboard diesel. When I would start it up it
would run right up to 2200 rpm's when in neutral. But when put in gear
it would only go up to 500 rpm's and take about 15-20 minutes before it
would go up to 1500 rpm's.Max rpm's shoould be about 2400. Then one
day I accidently left I forgot to open the raw water inlet value and
overheated the engine. I had a so-called mechanic come out and told him
the situation. He found water in the oil but said it was not a head
gasket problem but was due to water back siphoning through the exhaust.
He changed the oil several times to get the water out and said it
should be fine. When I went out again I still had the rpm problem so he
never even addresed that correctly. I decided to dive the prop and
removed and incredible amount of barnacles. However the rpm problem
persisted and I checked the oil again and found WATER in the oil AGAIN!
The engine does not overheat but am I right in thinking it is the head
gasket? If so are there any manuals that explain how to replace the
head gasket. I'm tired of paying overpaid mehanics who don't know what
they are doing and don't show up half the time.


From experience with an MD-11 with the same problems. First time it was the
water pump seals allowing water to run back into the engine because a PO had
repainted everything and painted over the weep holes on the shaft housing to
prevent what happened. The next time it was the exhaust manifold//water
jacket that had an eroded section so the water could seep by when cold. I
had it welded and then planed off to make a new surface, but it was so worn
that it didn't cure the problem. My fix was to replace it with a 3 GM 30F.

Leanne
s/v Fundy

I have a couple of MD6/MD7 manuals I have downloaded from the net.

They are one half to one and a half megs. If you want I will email them
to you. But they may take a looong time if you are on dial up.

Howard

wrote:
I have volvo penta md6b inboard diesel. When I would start it up it
would run right up to 2200 rpm's when in neutral. But when put in gear
it would only go up to 500 rpm's and take about 15-20 minutes before it
would go up to 1500 rpm's.Max rpm's shoould be about 2400. Then one
day I accidently left I forgot to open the raw water inlet value and
overheated the engine. I had a so-called mechanic come out and told him
the situation. He found water in the oil but said it was not a head
gasket problem but was due to water back siphoning through the exhaust.
He changed the oil several times to get the water out and said it
should be fine. When I went out again I still had the rpm problem so he
never even addresed that correctly. I decided to dive the prop and
removed and incredible amount of barnacles. However the rpm problem
persisted and I checked the oil again and found WATER in the oil AGAIN!
The engine does not overheat but am I right in thinking it is the head
gasket? If so are there any manuals that explain how to replace the
head gasket. I'm tired of paying overpaid mehanics who don't know what
they are doing and don't show up half the time.

thanks for any help

I had a similar sitution with my MD-7b and it was the head gasket...both
times! Changing the gasket is fairly easy if you are at all experienced with
mechanics. I recommend taking the head off with the exhaust manifold in
place. It's a little heavy but one person can handle it. The hardest part is
getting that two-bit water piping system from the water pump to the ex
manifold and then to the thermostate housing back together without leaks.
BTW..I switched to Yanmar, having had my fill of Volvo. Good luck.
"Howard" wrote in message
rvers.com...
I have a couple of MD6/MD7 manuals I have downloaded from the net.

They are one half to one and a half megs. If you want I will email them
to you. But they may take a looong time if you are on dial up.

Howard

wrote:
I have volvo penta md6b inboard diesel. When I would start it up it
would run right up to 2200 rpm's when in neutral. But when put in gear
it would only go up to 500 rpm's and take about 15-20 minutes before it
would go up to 1500 rpm's.Max rpm's shoould be about 2400. Then one
day I accidently left I forgot to open the raw water inlet value and
overheated the engine. I had a so-called mechanic come out and told him
the situation. He found water in the oil but said it was not a head
gasket problem but was due to water back siphoning through the exhaust.
He changed the oil several times to get the water out and said it
should be fine. When I went out again I still had the rpm problem so he
never even addresed that correctly. I decided to dive the prop and
removed and incredible amount of barnacles. However the rpm problem
persisted and I checked the oil again and found WATER in the oil AGAIN!
The engine does not overheat but am I right in thinking it is the head
gasket? If so are there any manuals that explain how to replace the
head gasket. I'm tired of paying overpaid mehanics who don't know what
they are doing and don't show up half the time.

thanks for any help

Thanks Howard, I do have the owner's manual but if you would be kind
enough I will take you up on your offer. My email is

Jerry

Howard wrote:
I have a couple of MD6/MD7 manuals I have downloaded from the net.

They are one half to one and a half megs. If you want I will email them
to you. But they may take a looong time if you are on dial up.

Howard

wrote:
I have volvo penta md6b inboard diesel. When I would start it up it
would run right up to 2200 rpm's when in neutral. But when put in gear
it would only go up to 500 rpm's and take about 15-20 minutes before it
would go up to 1500 rpm's.Max rpm's shoould be about 2400. Then one
day I accidently left I forgot to open the raw water inlet value and
overheated the engine. I had a so-called mechanic come out and told him
the situation. He found water in the oil but said it was not a head
gasket problem but was due to water back siphoning through the exhaust.
He changed the oil several times to get the water out and said it
should be fine. When I went out again I still had the rpm problem so he
never even addresed that correctly. I decided to dive the prop and
removed and incredible amount of barnacles. However the rpm problem
persisted and I checked the oil again and found WATER in the oil AGAIN!
The engine does not overheat but am I right in thinking it is the head
gasket? If so are there any manuals that explain how to replace the
head gasket. I'm tired of paying overpaid mehanics who don't know what
they are doing and don't show up half the time.

thanks for any help

JerryW,

Well that does help confirm what I thought. The Massachusetts Maritime
Academy near Boston offers a one day course where they do a tear down
of a westerbeke diesel. It's $150 and I'm taking it November 4. I
assume that it will be applicable to the volvo. They also offer a 4 day
course for $600 but it is from Monday -Thursday so that's out.
I have a 1977- 28 foot Islander sloop and I plan on moving up to a 34
ft boat in the next year or two so I really do not want to repower.
By the way Howard I have high speed cable.

Thanks for the replys guys. I'll you know how things turn out.



Jerry W wrote:
I had a similar sitution with my MD-7b and it was the head gasket...both
times! Changing the gasket is fairly easy if you are at all experienced with
mechanics. I recommend taking the head off with the exhaust manifold in
place. It's a little heavy but one person can handle it. The hardest part is
getting that two-bit water piping system from the water pump to the ex
manifold and then to the thermostate housing back together without leaks.
BTW..I switched to Yanmar, having had my fill of Volvo. Good luck.
"Howard" wrote in message
rvers.com...
I have a couple of MD6/MD7 manuals I have downloaded from the net.

They are one half to one and a half megs. If you want I will email them
to you. But they may take a looong time if you are on dial up.

Howard

wrote:
I have volvo penta md6b inboard diesel. When I would start it up it
would run right up to 2200 rpm's when in neutral. But when put in gear
it would only go up to 500 rpm's and take about 15-20 minutes before it
would go up to 1500 rpm's.Max rpm's shoould be about 2400. Then one
day I accidently left I forgot to open the raw water inlet value and
overheated the engine. I had a so-called mechanic come out and told him
the situation. He found water in the oil but said it was not a head
gasket problem but was due to water back siphoning through the exhaust.
He changed the oil several times to get the water out and said it
should be fine. When I went out again I still had the rpm problem so he
never even addresed that correctly. I decided to dive the prop and
removed and incredible amount of barnacles. However the rpm problem
persisted and I checked the oil again and found WATER in the oil AGAIN!
The engine does not overheat but am I right in thinking it is the head
gasket? If so are there any manuals that explain how to replace the
head gasket. I'm tired of paying overpaid mehanics who don't know what
they are doing and don't show up half the time.

thanks for any help